Flexible instrument

ABSTRACT

A remote control flexible instrument system, employing a shaft which supports a tool, is described in which the has proximal and distal ends with at least a portion thereof extending through a lumen of the human body so as to locate the shaft at an internal target site. A master station including an input device provides control of the instrument situated at a slave station. The master station can control at least one degree-of-freedom of the flexible instrument. A controller intercouples the master and slave stations and is operated in accordance with a computer algorithm that receives a command from the input device for controlling at least one degree-of-freedom of the catheter so as to respond in accordance with action at the input device. The flexible instrument further comprises a controlled flexible segment along the shaft, for controlled bending at the flexible segment to guide the shaft and to dispose the tool at an operative site.

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation-in-part of and claims thebenefit of priority from U.S. application Ser. No. 09/827,503, filedApr. 6, 2001, which is a continuation of U.S. application Ser. No.09/746,853, filed Dec. 21, 2000, which is a divisional of U.S.application Ser. No. 09/375,666, now U.S. Pat. No. 6,197,017, filed Aug.17, 1999, which is a continuation of U.S. application Ser. No.09/028,550 filed Feb. 24, 1998, now abandoned. This application is alsoa continuation-in-part of and claims the benefit of priority from U.S.application Ser. No. 09/783,637, filed Feb. 14, 2001, which is acontinuation of PCT/US00/12553 filed May 9, 2000, which claims thebenefit of priority of U.S. provisional patent application Serial No.60/133,407, filed May 10, 1999, now abandoned. This application is alsoa continuation-in-part of and claims the benefit of priority fromPCT/US01/11376 filed Apr. 6, 2001 which claims priority to U.S.application Ser. Nos. 09/746,853 filed Dec. 21, 2000 and 09/827,503filed Apr. 6, 2001. This application is also a continuation-in-part ofand claims the benefit of priority from U.S. application Ser. Nos.09/746,853 filed Dec. 21, 2000 and 09/827,503 filed Apr. 6, 2001. Thisapplication is also a continuation-in-part of and claims the benefit ofpriority from U.S. application Ser. No. 09/827,643 filed Apr. 6, 2001which claims priority to, inter alia, U.S. provisional application Ser.No. 60/257,869 filed Dec. 21, 2000 and U.S. provisional application Ser.No. 60/195,264 filed Apr. 7, 2000 and is also a continuation-in-part ofPCT/US00/12553 filed May 9, 2000 from which U.S. application Ser. No.09/783,637 filed Feb. 14, 2001 claims priority.

[0002] This application also claims the benefit of priority under 35U.S.C. §§119 and 120 to U.S. Provisional Application Serial No.60/293,346 filed May 24, 2001, U.S. Provisional Application Serial No.60/279,087, filed Mar. 27, 2001, U.S. Provisional Application Serial No.60/313,496 filed Aug. 21, 2001, U.S. Provisional Application Serial No.60/313,497 filed Aug. 21, 2001, U.S. Provisional Application Serial No.60/313, 495 filed Aug. 21, 2001, U.S. Provisional Application Serial No.60/269,203 filed Feb. 15, 2001, U.S. Provisional Application Serial No.60/269,200 filed Feb. 15, 2001, U.S. Provisional Application Serial No.60/276,151 filed Mar. 15, 2001, U.S. Provisional Application Serial No.60/276,217 filed Mar. 15, 2001, U.S. Provisional Application Serial No.60/276,086 filed Mar. 15, 2001, U.S. Provisional Application Serial No.60/276,152 filed Mar. 15, 2001, U.S. Provisional Application Serial No.60/257,816 filed Dec. 21, 2000, U.S. Provisional Application Serial No.60/257,868 filed Dec. 21, 2000, U.S. Provisional Application Serial No.60/257,867 filed Dec. 21, 2000, U.S. Provisional Application Serial No.60/257,869 filed Dec. 21, 2000.

[0003] The disclosures of all of the foregoing applications and U.S.Pat. No. 6,197,017 are all incorporated herein by reference in theirentirety.

[0004] This application further incorporates by reference in itsentirety the disclosures of the following U.S. Patent applications whichare being filed concurrently on the same date herewith, having thefollowing titles and docket numbers: 08491.7013—Surgical Instrument;08491.7014—Surgical Instrument; 08491.7015—Surgical Instrument;08491.7016—Surgical Instrument; 08491.7017—Surgical Instrument;08491.7018—Surgical Instrument; 08491.7019—Surgical Instrument;08491.0006—Flexible Instrument; 08491.0006—Flexible Instrument;08491.0007—Flexible Instrument; 08491.0008—Flexible Instrument;008491.0009—Flexible Instrument; 08491.0010—Flexible Instrument; and08491.0011—Flexible Instrument.

FIELD OF THE INVENTION

[0005] The present invention relates in general to a remote controlledflexible instrument comprising a flexible shaft, for introduction into abody cavity or body vessel to perform a medical procedure.

BACKGROUND OF THE INVENTION

[0006] Catheters are used extensively in the medical field in varioustypes of procedures, including invasive procedures. Minimally invasivesurgery involves operating through small incisions, through whichinstruments are inserted. These incisions are typically 5 mm to 10 mm inlength. Minimally invasive surgery is typically less traumatic thanconventional surgery, due, in part, to the significant reduction inincision size. Furthermore, hospitalization is reduced and recoveryperiods shortened as compared with conventional surgery techniques.Catheters may be tailored to a particular size or form, depending on theincision and the size of the body cavity or lumen.

[0007] Due to the small size of the incision, the bulk of the surgery isnot visible. Although the surgeon can have visual feedback from thesurgical site via a video camera or endoscope inserted into the patient,or via radiological imaging or ultrasonic scanning, the ability tocontrol the relatively simple laparoscopic instruments remainsdifficult. Even with good visual feedback, the surgeon's tactile andpositional senses are physically removed from the operative site,rendering endoscopic procedures slow and clumsy.

[0008] Current instrumentation, with forceps, scissors, etc., insertedinto the body at the end of long slender push rods is not fullysatisfactory. The use of such conventional instrumentation increasesoperative time, and potentially heightens risk. For example, tissue maybe injured when the laparoscopic tool moves outside the visual field.Moreover, there are limitations on the type and complexity of proceduresthat may be performed laparoscopically due, in part, to the limitationson the instruments that are used.

[0009] Development work has been undertaken to investigate the use ofrobotic work in surgery. Typically, these robotic systems use arms thatreach over the surgical table and manipulate surgical instruments. Theknown robotic systems are large, clumsy to operate and relativelyexpensive to manufacture. The presence of a robot at the surgical siteis problematic particularly when the robot is large and may impedeaccess to the patient during surgery.

SUMMARY OF THE INVENTION

[0010] The present invention features, at least in part, an improved,remote controlled surgical system that does not impede access to thepatient during surgery, yet is simple to operate. The present inventionprovides a surgical instrument system particularly adapted for a varietyof medical procedures, including minimally invasive surgery.

[0011] One aspect of the present invention provides a surgicalinstrument comprising a shaft having at least one controllably flexiblesegment and a tool mounted at a distal end of the shaft. The tool isinsertable into a subject. The instrument further comprises a shaftmount drivably coupled to the shaft at a proximal end of the shaft wherethe shaft mount is then drivably coupled to the tool through the shaft.The instrument also comprises a drive unit drivably coupled to the shaftmount. The drive unit is operable from a location remote from thesubject to control flexure of the flexible segment so as to controldisposition of the tool at an operative site.

[0012] Another aspect of the present invention provides a remotelycontrollable surgical instrument comprising a user input device forinputting a command. A slave station receives the command from the inputdevice. The user input device is remotely disposed from the slavestation. The slave station further comprises a mechanically drivablemechanism comprising a shaft having a proximal end, a distal endsupporting a tool and a flexible portion between the proximal and distalends. An electronic signal link is between the user input device and theslave station receives a the command from the input device beingcommunicated via the link, for controlling bending of the flexibleportion so as to controllably position the tool at an operative site ofa subject.

[0013] Another aspect of the present invention provides a remotelycontrollable catheter comprising a tube having a proximal end and adistal end. At least a segment of the tube is controllably flexible. Thecatheter also comprises a drivable bending mechanism mechanicallycoupled to and interactive with a controllably flexible segment of thetube. A computer remote from and interconnected to the bending mechanismhas a computer for receiving input from the user. The program directsthe bending mechanism to controllably flex the flexible segment of thetool according to the user input.

[0014] Another aspect of the present invention provides a cathetercomprising a shaft having proximal and distal ends and at least oneflexible segment along a length of the shaft. The distal end isinsertable within a body cavity or a vessel. A tool is supported at thedistal end of the shaft for performing a medical procedure. At least twocables extend along the shaft between the proximal and distal ends. Atleast one of the cables is associated with the flexible segment to theshaft and at least another of the cables is associated with a tool. Anelectronic control mechanism is drivably coupled to the cables where theelectronic control mechanism is capable of communicating drive signalsfrom a user input device to the cable to affect bending of the flexiblesegment and operation of the tool.

[0015] One aspect of the present invention provides a medical devicecomprising disposable mechanically drivable mechanism drivably coupledto a tool via a disposable shaft for insertion into a body vessel orcavity along a selected length of the shaft. The tool is operable tocarry out a medical procedure and the shaft is disposable together withthe mechanically drivable mechanism. A receiver receives a mechanicallydrivable mechanism. The medical device further comprises a drive unitcoupled to the receiver.

[0016] Another aspect of the present invention provides a medical devicecomprising a disposable implement comprising a disposable flexible shaftsupporting a tool at its distal end for insertion into a subject, and adisposable first drive interface drivably coupled with a tool to theshaft. The medical device further comprises a second drive interface,for drivably coupling the disposable implement with a drive unit. Thesecond drive interface is drivably engageable with a disposableimplement via the first drive interface.

[0017] Another aspect of the present invention provides a disposablemedical device comprising a disposable flexible shaft having a proximalend and a distal end. A disposable mechanically drivable interface isconnected to the proximal end of the shaft. A tool is mounted at thedistal end of the shaft. The device further comprises at least onedisposable cable drivably interconnected between the mechanicallydrivable interface in the tool. The mechanically drivable interface isinterconnected to a remotely disposed electronic control mechanism whichcontrols drive operation of the device.

[0018] Another aspect of the present invention provides a disposableelectronically controlled surgical instrument comprising a disposableflexible elongated shaft having a proximal end and a distal end on whichis mounted a tool. The proximal end of the shaft is connected to amechanically drivable interface. The disposable shaft includes at leastone disposable cable drivably interconnected between the mechanicallydrivable interface and the tool. The mechanically drivable interface isinterconnected to a remotely disposed electronic control mechanism whichcontrols drive operation of the device.

[0019] One aspect of the present invention provides a medical devicecomprising a flexible guide shaft having a distal end disposed at apredetermined location in the subject. The device comprises a flexibleinner shaft having a proximal end and a distal end supporting at itsdistal end a tool. The inner shaft is insertable into the guide shaft soas to dispose a tool at an operative site. The device further comprisesa drive unit coupled to the inner shaft for providing controlledactuation of the tool. The drive unit is remote controllably drivable bya user via a manually controllable device.

[0020] Another aspect of the present invention provides a medical devicecomprising a flexible inner shaft inserted within a flexible guideshaft. A tool is disposed at a distal end of the inner shaft forinsertion into a subject. A drive unit is coupled with an inner shaftand a guide shaft independently. The drive unit is capable ofindependently effecting movement of each shaft to at least one degree offreedom. A user input interface is remote from the drive unit, where theinput inference face is for remote controllably manipulating the innerand guide shaft.

[0021] Another aspect of the present invention provides a medical devicecomprising a flexible guide shaft having a distal end disposed at apredetermined location in a subject. A flexible disposable inner shafthas a proximal end and a distal end supporting at its distal end a tool.The inner shaft is insertable to the guide shaft so as to dispose thetool at an operative site. The drive unit is coupled with the innershaft for providing controlled actuation of the tool and controlleddeformation of one or more flexible portions of the inner shaft. Thedrive unit is remote controllably drivable by the user via a manuallycontrollable device. The proximal end of the inner shaft includes amechanically operative element drivably couplable to the drive unit. Themechanically operative element is disposable together with the tool as aunit.

[0022] One aspect of the present invention provides a medical devicecomprising a mechanically drivable mechanism coupled with a shaftincluding a flexible segment, where a distal end of the shaft supports atool insertion into a subject. A drive unit is coupled with amechanically drivable mechanism and disposed remotely from the sterilefield. The drive unit is for intercoupling drive from the drive unit tothe drivable mechanism. The drive unit is capable of activating theflexible segment via the mechanically drivable mechanism for actuationof the tool and positioning of the tool at the operative site within thesubject.

[0023] Another aspect of the present invention provides an apparatus foruse in a body cavity or vessel comprising a catheter having a proximalend and a distal end for placement in the body cavity or vessel. A toolis positioned at the distal end of the catheter. A flexible segment ispositioned between the distal and proximal ends of the catheter. Cablesextend from a drive unit through the flexible segment. The drive unit isoperable from a remote site and capable of bending the flexible segmentvia the cables for actuation of the tool.

[0024] Another aspect of the present invention provides a remotelydriven surgical instrument comprising an elongate flexible shaft havinga proximal end and a distal end supporting a surgical tool. The shaft isinsertable into a subject for disposition of the tool at an operativesite of the subject. An electronically controllable drive unit ismounted in a location remote from the subject. The remote drive unitincludes one or more motors drivably interconnected to the proximal endof a flexible shaft by one or more motor driven cables, which arereadily drivably interconnectable to and disconnectable from theproximal end of the flexible shaft.

[0025] One aspect of the present invention provides a robotic medicalsystem comprising a flexible instrument having flexible and distal endswith at least one flexible segment extending through a lumen of thehuman body. The at least one flexible segment is controllably bendableso as to locate a distal end of the shaft at an internal target site. Atool is carried at the distal end of the shaft for performing aprocedure. A master station includes an input device. A slave stationincludes a receiver for the catheter for controlling through thereceiver at least one degree of freedom of the catheter. A controller iscoupled between the master station and the slave station and is operatedin accordance with computer algorithm that receives a command from theinput device and for controlling the at least one degree of freedom ofthe catheter so as to respond in accordance with action at the inputdevice.

[0026] Another aspect of the present invention provides a method ofremotely controlling a catheter comprising providing a flexible shafthaving a distal end supporting a tool. The shaft includes at least onecontrolled flexible segment about the distal end capable of controlledvending for positioning the tool at an operative site. The methodcomprises inserting the shaft into an anatomic lumen where the flexibleshaft is adapted to conform to the configuration of the anatomic lumen.The method comprises mechanically driving, via a drive unit, a cablingsystem extending through the shaft and the at least one flexiblesegment. The at least one controlled flexible segment is activated byoperating the drive unit from a location remote from the shaft so as toaffect bending of the at least one flexible segment and thereby effectpositioning of the tool to a target site.

[0027] Another aspect of the present invention provides a flexibleinstrument system comprising a flexible shaft having a proximal end anda distal end. The distal end supports a tool. The shaft is insertableinto a subject so as to dispose the tool at an operative site. Amechanically drivable mechanism is disposed at the proximal end of theshaft. The mechanically drivable mechanism is capable of offering thetool via at least one flexible segment positioned along the shaft. Areceiver is supported in a fixed potion of the subject for receiving andstoring the shaft via the mechanically drivable mechanism in a positionto maintain the tool at the operative site. A computation systemreceives electrical control signals from a user input device forcontrolling the shaft.

[0028] Another aspect of the present invention provides a flexibleinstrument system comprising a medical implement having sufficientflexibility along a length thereof so as to at least flex and conform toa pathway in an anatomic vessel or cavity as the implement is insertedtherein. The medical implement comprises a tool for performing a medicalprocedure and a flexible shaft having proximal and distal ends. Theshaft supports the tool at the distal end and is insertable into asubject so as to dispose the tool at an operative site via controlledbending of at least one flexible segment positioned along the shaft. Themedical implement also comprises a mechanically drivable mechanismdisposed at the proximal end of the shaft. The system comprises a driveunit intercoupled with a medical implement and includes at least a firstcable intercoupled with a tool and at least a second cable intercoupledwith a shaft for controlling a bend at the at least one flexiblesegment.

[0029] Another aspect of the present invention provides a flexibleinstrument system comprising a drive unit for controlling operation of amedical implement. A mechanical actuation system extends from the driveunit. The medical implement has sufficient flexibility to conform to apathway in an anatomic vessel or cavity as the implement insertedtherein. The medical implement comprises a flexible shaft havingproximal and distal ends where the flexible shaft is insertable into asubject so as to dispose the distal end at an operative site. The shaftfurther comprises at least one controlled flexible segment actuating acontrolled bend. The medical implement also comprises a mechanicallydrivable mechanism disposed at a proximal end of the flexible shaft.

[0030] One aspect of the present invention provides a system forpreparing a cardiac valve comprising a flexible guide shaft extendingfrom a site outside a patient to an area about the cardiac valve. Aflexible inner shaft supports at its distal end a remotely controlledtool for performing a cardiac repair procedure. The inner shaft isreceived in the guide shaft for disposing the tool at the area about thecardiac valve. A retainer is positioned at the area of the cardiacvalve. The retainer is attached to an annulus of the cardiac valve andis closable via the tool to draw the annulus into a smaller diameter.

[0031] Another aspect of the present invention provides the method ofrepairing a mitral valve of the heart. The method comprises extending aguide shaft from a site outside the patient to a site adjacent themitral valve. The method comprises inserting a fiber through the guideshaft and securing the fiber about an annulus of the mitral valve whilethe heart is beating. The securing step includes introducing through theguide shaft a flexible inner shaft having a remotely controlled distaltool for securing the fiber about the annulus leaving opposite ends ofthe fiber exposed. The method for this comprises applying a force to thefiber ends so as to draw the annulus into a tighter diameter.

[0032] Another aspect of the present invention provides a system forremotely repairing a cardiac valve comprising a guide catheter extendingthrough an area of the human body where a distal end of the guidecatheter is disposed at an area about the cardiac valve. A fiber extendsabout a diameter of an annulus of the cardiac valve. The fiber isengaged with a diameter of the annulus and capable of drying the annulusto a smaller diameter. The system comprises a flexible working catheterreceived by the guide catheter, where the working catheter includes atool engageable with a fiber. A remote manipulator is controlled from asite remote from the body, for controlling the tool.

[0033] Another aspect of the present invention provides a method ofrepairing a mitral valve of the heart, comprising extending a guideshaft from a site outside the patient to a site about the mitra valve.The method comprises providing a ring of a first diameter where the ringis deformable and capable of matching a desired predetermined diameterof an annulus of the mitral valve. The ring is engaged with a guideshaft via a flexible inner shaft received by the guide shaft. The ringis secured about the mitral valve annulus while the heart is beating.The securing step includes engaging the ring about a circumference ofthe annulus via a remotely controlled tool supported at a distal end ofthe inner shaft. The annulus is drawn into the predetermined diameter.

[0034] Another aspect of the present invention provides a method ofrepairing a cardiac valve comprising providing a balloon supported on acatheter. A plurality of peripherally disposed anchor pins is supportedfrom an outer surface of the lumen where the anchor pins are tethered toeach other. The balloon is passed in a deflated state to an area aboutthe cardiac valve. The method comprises inflating the balloon to thrustthe anchor pins into an annulus of the cardiac valve. The tether istightened to pull the peripherally disposed pins into a smallerdiameter.

[0035] Another aspect of the present invention provides a method forrepairing a cardiac valve comprising providing a balloon and supportingand passing the balloon in a deflated state to an area about the cardiacvalve. A plurality of peripherally disposed anchor pins is disposed andarranged about an outer surface of the balloon. A tether is provided forintercoupling the anchor pins. The balloon is inflated once it ispositioned at the area about the cardiac valve, to thrust the anchorpins into a ring defining a base of the cardiac valve. A tether istightened to pull the peripherally disposed pins into a smallerdiameter.

[0036] Another aspect of the present invention provides a system forremotely repairing a cardiac valve comprising a flexible guide shaftextending to an area of the human body so as to locate a distal endthereof at an area about the cardiac valve. A delivery member, forsupporting an array of securing pieces at a distal end thereof, extendsthrough the flexible guide member. The array of securing pieces isintercoupled by a cable. A remote manipulator is controlled from aslight remote from the body, for controlling the delivery member toexpel the securing pieces in sequence about the cardiac valve annulus asthe valve is functioning. The remote manipulator is capable ofcontrolling a tightening of the cable to draw the annulus into a smallerdiameter.

[0037] Another aspect of the present invention provides a flexibleinstrument system for repairing an anatomic body part comprising a shafthaving sufficient flexibility along the length thereof so as to readilyflex and conform to a pathway in the anatomy as the shaft is insertedtherein. A drivable mechanism is disposed at a flexible end of the shaftcontrolling a tool supported at a distal end of the shaft. The shaft isinsertable into a subject so as to dispose the distal end of the shaftat an internal site of an anatomical body part. A retainer is attachedto an annulus at the anatomic body part where the retainer is closableso as to draw the annulus into a smaller diameter.

BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Numerous other objects, features and advantageous of theinvention should now become apparent upon a reading of the followingdetailed description taken in conjunction with the accompanying drawingsin which:

[0039]FIG. 1 is a simplified block diagram illustrating basic componentsof a system constructed in accordance with the present invention;

[0040]FIG. 2 illustrates further details of input devices at the masterunit;

[0041]FIG. 3 is a schematic diagram illustrating one embodiment of thepresent invention in which the flexible instrument system includesmultiple separate nested catheters;

[0042] FIGS. 3A-3C illustrate different forms of catheter control inaccording with aspects of the present invention;

[0043]FIG. 4 is an illustrative diagram showing the use of the catheterof the present invention in connection with mitral valve repair;

[0044]FIG. 5 is schematic diagram of the catheter system of the presentinvention as deployed through the urethra for a surgical procedure inthe bladder;

[0045]FIG. 6 is a perspective view of one embodiment of a systemembodying the catheter apparatus of the present invention;

[0046]FIG. 7 is a more detailed perspective view of the catheterapparatus;

[0047]FIG. 8 is an enlarged view of a portion of the catheter apparatusparticularly at the distal end section thereof;

[0048]FIG. 9 is a cross-sectional view through the catheter apparatus astaken along line 9-9 of FIG. 7;

[0049]FIG. 10 is a cross-sectional view through the catheter apparatusas the distal end section thereof, as taken along line 10-10 of FIG. 7;

[0050]FIG. 11 is a cross-sectional view similar to that illustrated inFIG. 9 for an alternate embodiment of the invention depictingdual-direction flexing;

[0051]FIG. 12 is one design of tool construction in accordance with thepresent invention employing inner and outer catheters and inner andouter cables;

[0052]FIG. 13 is a schematic diagram of the tool or mini-tool showingcertain parameters relating to position control;

[0053]FIG. 14 is a block diagram of the controller used with thetelerobotic system of this invention;

[0054]FIG. 15 is a block diagram of further details of the controllerparticularly details of the module board;

[0055]FIG. 16 is a block diagram of the control algorithm in accordancewith the present invention;

[0056]FIG. 17 is a schematic diagram illustrating one mechanism forproviding mitral valve repair employing a ring mechanism;

[0057]FIG. 18 illustrates schematically the concept of the presentinvention in connection with mitral valve repair;

[0058]FIG. 19 is a diagram of a heart muscle illustrating the positionof the mitral valve;

[0059]FIG. 20 illustrates further detail of the mitral valveconstruction as well as the catheter and tool used in the procedure;

[0060]FIG. 21 is a more detailed cross-sectional drawing of the portionof the mechanical member, particularly the means for tightening theretaining means;

[0061]FIG. 22 shows further details of the structure of FIG. 21;

[0062]FIG. 23 is a schematic illustration of a section of the mitralvalve ring showing the fiber and the securing of one end of the fiber;

[0063]FIG. 24 illustrates somewhat further detail of a means forretaining the catheter in position;

[0064]FIG. 25 is a diagram illustrating alternate means for holding thecatheter in place;

[0065]FIG. 26 illustrates a view of a mitral valve;

[0066]FIG. 27 is a schematic diagram of the mitral valve indicating thering area and leaflets;

[0067]FIG. 28 is a schematic illustration showing the mitral valveconstruction and a mechanical member for retaining and tightening;

[0068]FIG. 29 is schematic diagram of another technique for mitral valverepair employing a wire to be tightened like a lasso;

[0069]FIG. 30 is a schematic diagram illustrating a catheter and toolconstruction containing a tether cable and anchor elements within theinner catheter;

[0070]FIG. 30A shows a cable termination tool for crimping;

[0071]FIG. 30B shows a tool for cutting;

[0072]FIG. 31 illustrates a staple array of the present invention;

[0073]FIG. 32 illustrates the mitral valve construction as well as thestaple apparatus and technique of the present invention;

[0074]FIG. 33 is an illustration of the staple array when applied andsecured to the valve annulus;

[0075]FIG. 34 is a schematic illustration of an alternate embodiment forthe staple array;

[0076]FIGS. 35A and 35B illustrate another version of the inventionwherein the guide catheter is robotic;

[0077]FIG. 36 schematically represents a system of the present inventionfor repairing a mitral valve;

[0078]FIG. 36A shows a pin for anchoring;

[0079]FIG. 37 illustrates the anchoring system engaged with the mitralvalve;

[0080]FIG. 38 illustrates another version in accordance with theinvention employing a balloon with the balloon in a deflated state;

[0081]FIG. 39 schematically represents portions of the heart muscle andthe positioning of the balloon relative to the mitral valve;

[0082]FIG. 40 illustrates the balloon in its inflated state positionedat the mitral valve;

[0083] FIGS. 41A-41D depict still another form of catheter in accordancewith the present invention;

[0084]FIG. 42 is a perspective view of another embodiment of the presentinvention;

[0085]FIG. 42A is an enlarged detail perspective view of the tool;

[0086]FIG. 43 is an exploded perspective view of, in particular, theinterlocking modules of the flexible instrument system of FIG. 42;

[0087]FIG. 44 is a partially broken away rear elevational view of theinterlocking modules as seen along line 44-44 of FIG. 42;

[0088]FIG. 45 is a cross-sectional side view through the interconnectingmodules and as taken along line 45-45 of FIG. 42;

[0089]FIG. 46 is a cross-sectional plan view through the instrumentmodule taken along line 46-46 of FIG. 45;

[0090]FIG. 47 is a cross-sectional plan view taken through the basemodule of the system of FIG. 42, and as taken along line 47-47 of FIG.45;

[0091]FIG. 48 is a cross-sectional end view taken along line 48-48 ofFIG. 47;

[0092]FIG. 48A is a cross-sectional view taken along line 48A-48A ofFIG. 48;

[0093]FIG. 48B is a fragmentary plan view of a drive wheel engagementslot by itself as taken along line 48B-48B of FIG. 48A; and

[0094]FIG. 49 is a schematic perspective view showing mechanical cablingbetween the drive unit and the flexible instrument system.

DETAILED DESCRIPTION

[0095] The present invention provides a system for remotely controllinga flexible instrument for use in medical applications, typically foroperative or other medical procedures. The flexible instrument comprisesa shaft or a tube of sufficient dimensions for passing through a smallincision or natural body lumen or cavity and ultimately, for positioninga distal end of the shaft within the body at an internal target(operative) site. The flexible instrument can also support a tool at itsdistal end to allow more intricate medical procedures. A user or surgeoncan control the position of the shaft from a master station, allowingoperation from another part of the operating room, or even from anotherroom or another building. In one aspect of the invention, the shaft cancomprise one or more flexible segments, which a user can controllablybend, providing finer control in directing the shaft toward the targetsite. The control can result in, for example, a deflection or turning ofthe shaft, for guiding this shaft through or within various bodycavities or lumens. The controllable bending is also useful for moreprecise positioning of a distal end of the flexible instrument at adesired operative site.

[0096] Preferably, the flexible instrument is used to perform minimallyinvasive procedures. “Minimally invasive procedure,” refers herein to asurgical procedure in which a surgeon operates through small cut orincision, the small incision being sufficiently necessary to access theoperative site. In one embodiment, the incision length ranges from 1 mmto 20 mm in diameter, preferably from 5 mm to 10 mm in diameter. Thisprocedure contrasts those procedures requiring a large cut to access theoperative site. Thus, the flexible instrument is preferably used forinsertion through such small incisions and/or through a natural bodylumen or cavity, if necessary, so as to locate the catheter at aninternal target site for a particular surgical or medical procedure.Examples of such minimally invasive procedures include intravascularprocedures, such as the repair of a cardiac valve. The introduction ofthe flexible instrument into the anatomy may be by percutaneous orsurgical access to a lumen or vessel, or by introduction through anatural orifice in the anatomy.

[0097]FIG. 1 is a block diagram schematically illustrating the threemain components of the remote control system of the present invention. Asurgeon or user can input control actuations at master station 1,typically through an input device (not shown). Slave station 3 isseparate and remote from the master station and controls the motion ofthe flexible instrument, in accordance with the user input from masterstation 1. Master station 1 and slave station 3 may be in relativelyclose proximity to each other, such as in the same operating room, orcan be displaced from each other by miles. Controller 2 provides atelecommunications or electronic communications link coupled between themaster station and the slave station. Controller 2 typically includes acomputer. Controller 2 receives a command from the input device ofmaster station 1 and relays this command to slave station 3.

[0098]FIG. 6 is a schematic of the remote control system of the presentinvention. The system includes: (1) A master station comprising a userinterface or surgeon's interface 11; (2) A slave station comprising aflexible instrument including shaft 30 which supports tool 18. Shaft 30is connected to and is controllable from mechanically drivable mechanism26, which in turn is engageably received by receiver 24, both of whichare mechanically driven by drive unit 13, (alternatively mechanicaldrive 13); and (3) a controller or computation system 12 to translate auser's commands from user interface 11 to drive unit 13, which thendrives the articulations of shaft 30 and tool 18. FIG. 6 illustrates asystem where a user or surgeon can control shaft 30 and tool 18 bymanipulating interface handles 30A of user interface 11. The movement ofhandle 30A causes responsive movement of tool 18 through thecoordinating action of computation system 12. For example, tool 18 canbe a pair of graspers, scissors, staplers, etc. and manipulation ofhandle 30A can cause the jaws of tool 18 to open and close.

[0099] Surgeon's interface 11 is in electrical communication withcomputing system 12, which is, in turn, in electrical communication withdrive unit 13. In one embodiment, drive unit 13 comprises a plurality ofmotors. The drive unit 13 is in mechanical communication with shaft 30via conduit 23, which houses a plurality of mechanical cables driven bythe plurality of motors in drive unit 13. In one embodiment, drive unit13 is solely in mechanical communication with shaft 30. Because of themechanical communication with shaft 30, the electromechanical componentsin drive unit 13 are disposed in an area remote from the operative site,and preferably in an area outside the sterile field. Preferably, objectsthat are difficult to sterilize, e.g. motors or electromechanicalcomponents, are kept at a sufficient distance from the patient to avoidcontamination. This distance is readily ascertainable by doctors,nurses, and other appropriate medical professionals. In one embodiment,the sterile field has the rest surface of the operating table as itslower boundary. Thus, drive unit 13 is preferably located below theplane of the sterile field, i.e. below the rest surface of the operatingtable. The patient or subject may be further protected from drive unit13 with a sterile barrier, such as a sterile cloth. With respect to thedrive unit, such as drive unit 13 in FIG. 6, reference is made toco-pending provisional application No. 60/279,087, which is incorporatedby reference herein. In accordance with the system of FIG. 6, all of thedrive motors in drive unit 13 are disposed away from the sterile fieldand thus the need for a sterile barrier is eliminated. Furthermore,since all of the motors and electronics are within a single,self-contained unit, design, testing and manufacturing of the system isgreatly simplified.

[0100] Accordingly, one aspect of the present invention provides a driveunit capable of remotely driving articulation of a flexible instrument,where the drive unit is remote from the subject and the flexibleinstrument. The slave station of the present invention employs, to alarge part, a mechanical arrangement that is effected remotely andincludes mechanical cables and flexible conduits coupling to a remotemotor drive unit. This provides the advantage that the instrument ispurely mechanical and does not need to be contained within a sterilebarrier. The instrument may be autoclaved, gas sterilized or disposed intotal or in part. In FIG. 6, drive unit 13 mechanically drives theflexible instrument (comprising shaft 30 and tool 18) through conduit23, receiver 24 and mechanically drivable mechanism 26 (alternativelyknown as mechanically drivable interface or shaft mount). Conduit 23houses a plurality of separate mechanical cables to mechanically connectdrive unit 13 with receiver 24. The mechanical cables physically contactand drive the motions of shaft 30 and tool 18. Conduit 23 is engageableand disengageable with drive unit 13, i.e. attachable and detachable(see discussion of FIG. 49, below). Although two conduits 23 aredepicted here, it is understood that more or fewer conduits may be used,depending on the particular application. In one embodiment, drive unit13 comprises a plurality of motors, which drive the mechanical cablesextending through conduit 23 and terminating at receiver 24. Receiver 24interlockably receives mechanically drivable interface 26, which engagesa separate set of cables extending through shaft 30 and at least onecable line operating tool 18. Thus, engaging drivable interface 26 withreceiver 24 provides a mechanical (physical) connection from drive unit13 to control certain motions of shaft 30 and tool 18. Receiver 24,which is supported by a carriage, is capable of moving along a linearpath represented by the arrow 22 via rails 25.

[0101] Cables in conduit 23 also mechanically drives the translation ofreceiver 24 along rails 25. The rails, and thus the linear translationextend at an acute angle with respect to the operating table, as well asthe subject. This angular arrangement disposes the flexible instrumentsystem in a convenient position over the patient. This arrangement alsominimizes the number of components that operate within the sterilefield, as drive unit 13 is maintained at a location remote from thesterile field.

[0102]FIG. 49 shows a schematic perspective view of the cabling pathwayfor mechanically coupling one of an array of motors of a drive unit witha tool supported on a distal end of a shaft. In general, the cablingpathway comprising a plurality of mechanical cables extends from thedrive unit to the receiver. Another separate set of mechanical cablesconnects the mechanically drivable mechanism, situated at a proximal endof the shaft, to the tool and any controlled flexible segmentspositioned along the shaft. Interlocking the receiver with themechanically drivable mechanism results in connecting the two separatesets of mechanical cables, thereby extending the cabling pathway fromthe drive unit to the distal end of the shaft. Thus, each of themechanically drivable mechanism and the receiver can be considered as acoupler, which interlocks or couples with each other.

[0103] More specifically, FIG. 49 shows drive motor 675 positionedwithin a drive unit, such as drive unit 13 of FIG. 6. The first cablingpathway comprises a set of cabling, which engages with and extends fromdrive motor 675 through idler pulley 682. The cables continue throughidler pulleys 630 and 632 to drive wheel 622, which resides in receiver506 (equivalent to receiver 24 of FIG. 6). A second separate set ofcables extends about the drive wheel 624, guided by cam 626 andcontinues through flexible instrument shaft 528. Tool 534 links to shaft528 via joint 601, which provides a wrist pivot about axis 532 in thedirection of arrows J4. The two separate sets of cables are interlockedby interlocking drive wheel 622 of receiver 506 with drive wheel 624 ofmechanically drivable mechanism 526 (equivalent to drivable mechanism 26of FIG. 6). Specifically, the interlocking involves slotting a blade 606into a corresponding slot within wheel 624 (see further discussion ofFIG. 43 below).

[0104] In one embodiment, the interlocking mechanism can comprise amagnetic attachment, where a first series of magnets in the mechanicallydrivable mechanism interacts with a second series of magnets in thereceiver. Each series of magnets can couple with the mechanical cables.

[0105]FIG. 49 also shows the output of motor 675 at a coupler pulley677, which is adapted to rotate with an output shaft of the motor. Therotational arrow 680 indicates this rotation.

[0106] For the sake of simplicity, FIG. 49 only illustrates one cablingpathway. It can be appreciated that several other cabling pathways canbe constructed and arranged to control other motions of the shaft andtool through other motors of the drive unit.

[0107] Regarding the interface 11, computer system 12 and drive unit 13,reference is also made to co-pending application PCT Serial No.PCT/US00/12553 filed May 9, 2000, and U.S. Provisional ApplicationSerial No. 60/279,087 filed Mar. 27, 2001, both of which areincorporated by reference herein in their entirety.

[0108] A more detailed discussion of the master station, the slavestation and computation system or controller 12 is provided below.

Master Station

[0109]FIG. 2 schematically depicts the components of master station 1.Master station 1 can include any one or a combination of input devicesA-E and a display F. Input device A is a point-and-touch device. Inputdevice B is a computer mouse. Input device C is a pointing device thatmay employ a pen or stylus. Input device D is a joystick. Input device Eis a hand interface, that provides finer control of the shaft, or a toolpositioned at the distal end of the shaft.

[0110] In one embodiment, input device E features handles that controlthe motion of the shaft and a tool. Referring back to FIG. 6, the masterstation features input device 11 comprising handles 30A. Handles 30A areheld by the surgeon, who can then torque, translate or rotate cathetermember 30 and tool 18 by performing the corresponding motions on handles30A. A rotation of a handle 30A via rotation of the surgeon's hand cancontrol rotation of, for example, the outer shaft 32 about the co-axis.Flexing or bending of flexible section 42 can be controlled by thesurgeon flexing his hand at the wrist and activating flex cable 52, asshown in FIG. 8 (see discussion of FIG. 8, below). A surgeon canmanipulate tool 18 by, for example, closing and opening the jaws ofhandles 30A to simulate opening and closing of jaws of tool 18.

[0111] Reference may also be made to copending application docket number08491-7018, filed of even date herewith, which discloses other detailsof a master station input device (master positioner) that may be used incarrying out the control described herein.

[0112] Display F provides a direct video image of the site surroundingthe distal end of the shaft. An endoscope supporting a camera isinserted into the body of a subject, providing the video feed of theoperative site. The camera can be mounted on or housed at the distal endof the shaft. The camera can provide a view of the operative site, ormay be positioned away from the site to provide additional perspectiveon the surgical operation.

[0113] Other detection systems may be used for providing differentimages useful in assisting the surgeon in performing the medicalprocedure. Thus, various signals may be utilized in conjunction with orin alternative to the video image, such as ultrasound (echocardiography,Doppler ultrasound), angiography, electrophysiology, radiology or magnetresonance imaging (MRI). Also, an audio signal could be used for guidingthe shaft. These detection techniques can be operated with the flexibleinstrument of the present invention to enhance guidance of the shaft tothe site as well as manipulation at the site.

[0114] In association with the input devices of FIG. 2, there arevarious feedback techniques can be used for feeding certain parameterssensed at the slave station back to the master station. The followingare parameters that may be sensed, including but not limited to:

[0115] 1. Force.

[0116] 2. Position.

[0117] 3. Vibration.

[0118] 4. Acoustics, auditory.

[0119] 5. Visual.

[0120] 6. Neurological stimulus.

[0121] 7. Electropotential

[0122] 8. Biochemical sensing.

Controller

[0123] As discussed previously, FIG. 6 illustrates a computer system 12,which interfaces the surgeon interface 11 and drive unit 13 of the slavestation. The drive unit 13 contains a series of motors that controlcables coupled by way of conduit 23 to control certain movements of thecatheter apparatus. The controller 12, depicted in FIG. 6 essentiallylinks the slave station to the surgeon interface. The user input deviceelectronically sends commands, which are translated by the controllerand sent to drive unit 13. Drive unit 13 then mechanically effects themotion of the shaft, particularly the flexible segment and the tool.

[0124]FIGS. 14 and 15 are block diagrams of an embodiment of a motorcontrol system that may be employed in a drive unit of the presentinvention. Regarding the master station side, there is at least oneposition encoder associated with each of the degrees-of-motion ordegrees-of-freedom. At least some of these motions are associated with amotor that may be represented by a combination of motor and encoder on acommon shaft. Thus, controlling the motor ultimately controls suchparameters as a force feedback to the master station. The present systemcan comprise a multiaxis, high performance motor control system, whichcan support anywhere from 8 to 64 axes simultaneously using eithereight-bit parallel or pulse width modulated (PWM) signals. The motorsthemselves may be direct current, direct current brushless or steppermotors with a programmable digital filter/commutator. Each motoraccommodates a standard incremental optical encoder.

[0125] The block diagram of FIG. 14 represents the basic components ofthe system. Host computer 700 is connected by digital bus 702 tointerface board 704. Host computer 700 can be, for example, an Intelmicroprocessor based personal computer (PC) at a control stationpreferably running a Windows NT program communicating with the interfaceboard 704 by way of a high-speed PCI bus 702 (5.0 KHz for eight channelsto 700 Hz for 64 channels) The PC communicates with a multi-channelcontroller electronic card, providing up to 28 axes of motion control,each with a 1.5 kHz sampling rate. The controller is efficient, scalableand robust.

[0126] Communication cables 708 intercouple interface board 704 to eightseparate module boards 706. Interface board 704 can be a conventionalinterface board for coupling signals between digital bus 702 andindividual module boards 706. Each module board 706 includes four motioncontrol circuits 710, as illustrated in FIG. 15. Each circuit 710 canbe, for example, a Hewlett-Packard motion control integrated circuit,such as an IC identified as HCTLL 100.

[0127]FIG. 15 depicts a further sub unit of this system, particularly apower amplifier sub unit 712. Power amplifier sub unit 712 is based onNational Semiconductor's H-bridge power amplifier integrated circuitsfor providing PWM motor command signals. Power amplifier 712 isassociated with each of the blocks 710, which couples to a motor X.Associated with motor X is encoder Y. Although the connections are notspecifically set forth, it is understood that signals intercouplebetween block 710 and interface 704 as well as via bus 702 to hostcomputer 700.

[0128] The motor control system may be implemented in two ways. In thefirst method the user may utilize the four types of control modesprovided by the motor control sub unit 706: positional control;proportional velocity control; trapezoidal profile control; and integralvelocity control. The use of any one of these modes can involve simplyspecifying desired positions or velocities for each motor, and necessarycontrol actions are computed by motion control IC 710 of the motorcontrol sub unit, thereby greatly reducing the complexity of the controlsystem software. However, in the case where none of the onboard controlmodes are appropriate for the application, the user may choose thesecond method in which the servo motor control software is implementedat the PC control station. Appropriate voltage signal outputs for eachmotor are computed by the PC control station and sent to the motorcontrol/power amplifier unit (706, 712). Even if the computation load ismostly placed on the PC control station's CPU, the use of highperformance computers as well as high speed PCI bus for data transfercan overcome this problem.

[0129]FIG. 16 describes the overview of the control algorithm for thepresent invention, mapping out motions of the catheter to that of thesurgeon's interface handle in three-dimensional space. Such precisemapping can create the feel of the tool being an extension of thesurgeon's own hands. The control algorithm can assume that both thesurgeon's interface as well as the catheter always starts at apredefined position and orientation, and once the system is started, itrepeats a series of steps at every sampling. The predetermined positionsand orientations, relate to the initial positioning at the masterstation.

[0130] First, the joint sensors (box 435), which are optical encoders inthe present embodiment, of the surgeon's interface system are read, andvia forward kinematics (box 410) computation of the interface system,the current positions (see line 429) and orientations (see line 427) ofthe interface handle can be performed. The translational motion of thesurgeon's hand motion is scaled (box 425) whereas the orientations arekept identical, resulting in desired positions (see line 432) andorientations (see line 434) of the catheter's tool. The results are theninputted into the inverse kinematics algorithms for the catheter's tool,and finally the necessary joint angles and insertion length of thecatheter system are determined. The motor controller (box 420) thencommands the corresponding motors to positions such that the desiredjoint angles and insertion length are achieved.

[0131]FIG. 16 provides an initial start position for the handle,indicated at box 440. The output of box 440 couples to a summationdevice 430. The output of device 430 couples to scale box 425. Initialhandle position 440 is established by first positioning the handles atthe master station so as to establish an initial master station handleorientation in three dimensional space. Initial handle position 440 isthen compared to the current handle position at device 430. The outputfrom device 430 is then scaled by box 425 to provide the desired toolposition on line 432 coupled to the catheter inverse kinematics box 415.

Slave Station

[0132] The slave station comprises a flexible instrument, e.g. a shaftoptionally supporting a tool at its distal end, for insertion into asubject. In one embodiment, the flexible instrument is a catheter.“Catheter” as defined herein refers to a shaft adapted for, but notnecessarily limited to, insertion into a subject, and more particularlyfor insertion into natural body lumens, canals, vessels, passageways,cavities or orifices. The shaft is typically tubular, but any elongateshaft may be adaptable for insertion into the subject. The shaft can besolid or hollow. A subject can be a human, an animal, or even individualorgans or tissues that are dead or living.

[0133] The introduction of the flexible instrument into the human oranimal body, may be by percutaneous or surgical access to a lumen orvessel, or by introduction through a natural orifice in the body. Inthis regard, examples of natural lumens include body vessels such as ablood vessel (artery, chamber of the heart or vein), urinary systemvessels (renal collection ducts, calix, ureter, bladder or urethra),hepatobilliary vessels (hepatic and pancreatic ducts, chyle ducts;common or cystic duct), gastrointestinal tract (esophagus, stomach,small and large intestine, cecum and rectum), gynecological tract(cervix, uterus, fallopian tube or milk ducts and mammary canals ofbreast), nasopharynx (eustacean tube, sinuses, pharynx, larynx, trachea,bronchus, bronchiole, tear duct) seminal vesicle, spinal canal, orventricles of the brain. Examples of a natural orifice include oral,rectal, nasal, otic, optic, or urethral orifices.

[0134] The shaft can be constructed from a standard 9 French (2.67mmdiameter) coronary guiding catheter.

[0135] The shaft may support various forms of tools, typically at itsdistal end. As depicted in FIG. 6, a user can manipulate tool 18 along asingle axis of motion where tool 18 is, for example, a grasper, scissorsor general mechanism (such as a stapler or clip applier). It is easilyunderstood by those of ordinary skill in the art, however, that toolsmay be located at a position other than the distal end of the shaft.Preferably the tools aid in carrying out various surgical or medicalprocedures, including, but not limited to:

[0136] 1. Grasp;

[0137] 2. Cut/lyse/puncture;

[0138] 3. fill/drain;

[0139] 4. Secure (suture, staple, anchor);

[0140] 5. Implant, i.e., any procedure that leaves an object in the bodyafter withdrawal of the flexible instrument;

[0141] 6. Remove;

[0142] 7. Deliver e.g. drug/therapeutic agents;

[0143] 8. Hemostasis;

[0144] 9. Anastomosis;

[0145] 10. Repair/reconstruct;

[0146] 11. Dilate/constrict/occlude;

[0147] 12. Retraction, e.g. backward or inward movement of an organ orpart;

[0148] 13. Coagulate;

[0149] 14. Laser application;

[0150] 15. Heat/cool;

[0151] Exemplary objects implanted in a subject include staples, tacks,anchors, screws, stents, sutures, and a variety of other objectsimplanted by physicians and medical professionals.

[0152] The procedure of delivering (procedure 7, above) can furtherinclude delivery of agents including, but not limited to:

[0153] 1. Adhesives.

[0154] 2. Cryonics.

[0155] 3. Drugs.

[0156] 4. Biologic agents.

[0157] 5. Radioactive elements.

[0158] 6. Bulking agents.

[0159] Furthermore, the flexible instrument can be used as a sensor.Parameters that may be sensed include, but are not limited to:

[0160] 1. Force.

[0161] 2. Pressure.

[0162] 3. Electrophysiological signals.

[0163] 4. Chemical, oxygen, Ph, blood gas.

[0164] 5. Temperature.

[0165] 6. Vibration.

[0166] The slave station also comprises a drive unit capable ofarticulating the flexible instrument, particularly the shaft and thetool. The drive unit is to drivably coupled to a receiver for receivingthe mechanically drivable mechanism. In one embodiment, this couplingoccurs via cables. The drive unit is electronically controllable fromthe master station, as there is an electronic link between the driveunit and a user input device of the master station.

[0167] When the receiver receives the mechanically drivable mechanism,the drive unit then has a direct pathway for controlling operation ofthe shaft and tool. If the shaft has a controlled flexible segment, thedrive unit is capable of activating or bending the flexible segment viathe mechanically drivable mechanism, for actuation of the shaft, thetool and positioning of the tool at an operative site within thesubject. In one embodiment, drive unit is capable of bending theflexible segment via a first set of cables which couple the drive unitto the receiver, and a second set of cables which drivably couple themechanically drivable mechanism to the flexible segment and the tool.

[0168] One aspect of the present invention provides a remote controlledouter (guide) catheter having a distal end disposed at or in an areaabout an operative site, preferably in the immediate area of anoperative site. A coaxial inner (working) catheter nested within theouter catheter can then be used to perform the surgical or medicalprocedure. Previous surgical procedures involve insertion of a trocar orcannula into the subject at a relatively short depth to provide anopening for receipt of the catheter, which is then guided to theoperative site. Typically the catheter is not disposed at the immediatearea around the operative or target site. Thus, if the surgeon needs asecond catheter, the first catheter must be withdrawn and the secondcatheter is guided to the target site. Such repeated insertions canaggravate trauma experienced by the patient.

[0169] The feature of the present invention, on the other hand, employsan outer catheter disposed at the target site, which allows more thanone shaft to be inserted and withdrawn with minimal irritation or traumaexperienced at the passageway leading to the operative site. In oneembodiment, the outer catheter housing a coaxial inner catheter isdisposed at the target site. The inner catheter can immediately functionat the operative site. If a second inner catheter is required, the firstinner catheter can be quickly withdrawn through the outer guide catheterand the second inner catheter inserted through the outer catheter withminimal injury to the subject.

[0170] A feature of this aspect of the present invention allows coaxialmultiple shafts to be remote controlled independently of each other.FIG. 3 depicts a system of remote controlled coaxial catheters. Thissystem employs three coaxial or nested catheters L1-L3. Dashed line Irepresents an incision or entry point of the patient. FIG. 3 alsoillustrates computer controls C1-C3, which are outside of and remotefrom the patient. “Remote from the patient” refers herein to anylocation outside the sterile field. Computer controls C1-C3 areassociated with corresponding actuators A1, A2 and A3, (i.e. driveunits) which in turn are associated with shafts L1-L3, respectively.Thus, in FIG. 3, for example, the controller C1 controls an actuator A1which, in turn, controls a certain action or movement of the outer shaftL1. Those of ordinary skill in the art would readily appreciate thatonly one computer can be used with software capable of independentlycontrolling actuators A1-A3. In another embodiment, shafts L1-L3 can beindependently controlled by one actuator, which independently drivesspecific cables leading to each of shafts L1-L3. Ultimately, the presentinvention allows shafts L1-L3 to be remote controlled independently fromeach other. For example, shaft L1 can remain stationary while shaft L2undergoes linear translations or rotations about the co-axis. The distalend of shaft L3 can also carry out these motions as well as a bend orflex independent of shafts L1 or L2. Shaft L2 can be controlled to, forexample, provide a rotational movement so as to enable rotation of adistal tool. The control of a tool supported at a distal end of a shaftis independent of the motions of shafts L1-L3. Alternatively, all shaftsL1-L3 can undergo a simultaneous bend or deflection at a singleoperative segment or flexible segment, labeled as 0 in FIG. 3.

[0171]FIG. 7 illustrates the outer and inner shafts. In FIG. 7, shaft 30comprises an outer shaft 32 housing and coaxial with inner shaft 34.Outer shaft 32 and inner shaft 34 extend from and within mechanicallydrivable interface 26. Interface 26 mechanically couples a drive unit(shown in FIG. 6) with shaft 30. Interface 26 further comprises a seriesof control elements, such as pulleys 64 and 72, which run cable lines 52and 28, and gears 60 and 68 for controlling rotation of the shafts.

[0172] The rotation of outer shaft 32 and inner shaft 34 about theco-axis can be controlled independently. Control element 60, or gear 60in interface 26 encircles outer shaft 30 and controls the rotationalposition of guide shaft 32 in the direction indicated by rotationalarrow 65. Gear 68 in interface 26 encircles inner shaft 34. Controlelement 68 controls the rotational position of the inner shaft 34 in thedirection indicated by rotational arrow 69. Rotational arrows 65 and 69indicate rotation about the “shaft lumen axis”, i.e. the axis tangentialto the cross section of the shaft lumen.

[0173] If a tool were supported at the distal end of inner shaft 34,control element 68 would control the rotational position of the toolabout the shaft lumen axis as well. If the distal end were flexed, theshaft would curve and rotation of the shaft would cause the tool totrace a circle, and not cause the tool to rotate about its internalaxis. As described below, another control can be positioned in themechanically drivable interface for solely controlling the toolindependent of the shaft controls.

[0174] Another aspect of the present invention provides a remotecontrolled flexible instrument capable of controlled bending, ascontrolled by a user at a master station. A flexible instrumentcomprises a shaft having at least one section that is flexible.“Flexible” refers herein to a material that is inherently andsufficiently deformable to readily pass atraumatically through a naturalbody lumen, cavity, vessel, orifice and the like. In one embodiment, theshaft is sufficiently flexible to readily flex and/or conform to apathway in an anatomic vessel, lumen, cavity or the like. Non-flexibleor rigid catheters can be distinguished from flexible instruments by thefollowing test. By knowing the dimensions of a rigid catheter and thepoint of entry into the subject, one can calculate the position of thecatheter end point inside the subject. In contrast, even if thedimensions and point of entry of a flexible shaft were known, theposition of its end point within the subject cannot be calculated withprecision because the flexible shaft may bend.

[0175] Flexible instruments of the present invention can also bedistinguished from other known catheters that mimic bending motionssolely through a series of rigid sections linked by joints. Thus, a“bend” is not the result of a deformation of the catheter material butby the pivoting or rotation of two rigid sections about a joint. Incontrast, flexible instruments of the present invention include at leastone flexible segment that is bendable without requiring the use ofjoints. The bending is remotely controlled, allowing deflection at theseflexible segments away from the lumen axis of the segment. Bending inthis sense is possible by choice of inherent flexibility of theinstrument coupled with an induced deflection at the flexible segment.Inherent flexibility can be achieved by choice of a deformable material,such as. Inherent flexibility can also be achieved by designedconstruction using a more rigid material, for example carving outsegments of the material, i.e. slotting the material, such that thematerial is sufficiently thin for bending. Of course, the flexibleinstrument can comprise rotatable or pivotable joints, but the flexiblecapability is not the result of employing such joints, but by thedeformability of the shaft material. In one embodiment, the bending isremotely controlled via a drive unit drivably coupled to the receiverfor receiving a mechanically drivable mechanism or shaft mount. Theshaft mount is then drivably coupled to the controlled flexible segment,thereby providing a drivable bending mechanism

[0176] Those of ordinary skill in the art can appreciate that the shaftcan be tailored for a particular body lumen. Factors of the shaftconstruction include resiliency of the walls of the lumen, curvature ofthe passageway, location of the target site, diameter of the lumen, etc.For example, a shaft for passing through a colon can be, but is notnecessarily, manufactured from a material that is less deformable than ashaft for passing through a small, delicate blood vessel. Lumens thatpresent passageways of high curvature may also require a more easilydeformable, and thus more flexible, shaft than does a relativelystraight lumen. Deformability of the shaft can also be tailored byvarying the dimensions, particularly the diameter, of the shaft.

[0177] In this aspect of the invention, a user can controllably bend orflex at least a section of the flexible instrument. In one embodiment,this controlled bend can be provided by a shaft having at least oneflexible segment, alternatively a controlled flexible segment. Bymanipulating controls at the master station, a user can induce a bend inthe shaft at the flexible segment. Preferably, the bend at the flexiblesegment is actuated mechanically, thus distinguishing this aspect of thepresent invention from prior art catheters where the bends are inducedelectrically. For example, U.S. Pat. No. 5,238,005 describes a bendingmechanism caused by varying the electrical resistance through a cathetermaterial having a negative coefficient. Heating one area of a catheterby increasing its electrical resistance results in contraction of thatarea, causing the catheter to deflect toward the contracted area. Incontrast, the present catheter responds to mechanical forces.

[0178]FIGS. 7 and 8 illustrate one embodiment of a controlled flexiblesegment. FIG. 7 shows controlled flexible segment 42 residing betweenproximal end 36 and distal end 38 of shaft 30. It is understood,however, that flexible segment 42 can be positioned on any portion ofshaft 30. FIG. 8 provides an expanded view of flexible segment 42 andillustrates one construction of flexible segment 42. Here, flexiblesegment 42 is constructed by providing inner shaft 34 as a flexiblematerial nested within outer shaft 32. Outer shaft 34 is split intorigid proximal and distal sections 36 and 38, both encircling innershaft 34. Thus, flexible segment 42 is the gap between proximal anddistal sections 36 and 38. Shrink-wrap pieces 44 and 45 extend over therespective facing ends of the proximal and distal shaft sections 36 and38 and adhere these facing ends to the flexible inner shaft.

[0179] Alternatively, flexible segment 42 may be in the form of a metalcoil of diameter similar to the diameter of outer shaft sections 36 and38.

[0180] Although FIG. 8 illustrates outer shaft 32 as being rigid, it canbe appreciated that outer shaft 32 can be constructed of a flexiblematerial as well, although its flexibility is preferably less than thatof inner shaft 34.

[0181] Referring to both FIGS. 7 and 8, the bending of flexible segment42 is controlled through flex wire 52 extending from mechanicallydrivable mechanism 26 and through flexible segment 42, terminating atpoint 54 of distal end 38 (see FIG. 8). Flex wire 52 is preferablydisposed between inner shaft 34 and outer shaft 32. FIG. 8 showstermination point 54 residing on the outer surface of distal end 38,although conceivably other surfaces of distal end 38 can serve astermination points. The other end wire 52 resides within drivablemechanism 26 on control pulley 64. Turning pulley 64 has the effect ofpulling wire 52 in a direction parallel to shaft 30 pointing towardsdrivable mechanism 26. Because wire 52 is terminated at 54, this pullcauses the distal shaft section 38 to deflect in a direction indicatedby the arrow 55, as shown in FIG. 7.

[0182] More than one flex wire can be spaced about the circumference ofouter shaft 32 to allow bending along multiple directions different fromarrow 55 yet orthogonal to shaft 30. For example, FIG. 11 illustrates anembodiment where two cables actuate bending the bending. FIG. 11 is across-sectional view of outer shaft 32 receiving inner shaft 34 attermination point 52. Two cables 52 A and 52 B terminate on outer 32 onopposite sides of distal shaft section 38. Cables 52A and 52B may bemanipulated so as to deflect the distal shaft section in oppositedirections, in a manner described previously. Those of ordinary skill inthe art can readily appreciate that employing multiple cables results ina shaft capable of deflecting in any number of directions.

[0183] If inner shaft 34 supports a tool at its distal end, the bendingmotions, along with the rotation about the co-axis, serves to place thetool at any place in three-dimensional space. Another control element,i.e. pulley 72 controls cable 28, which extends through the hollow areaof inner shaft 34, thereby allowing control of a specific tooloperation. Depending on the complexity of the device, one or more cablesleading to the tool may be required. In one embodiment, FIG. 12 depictsa distal end of shaft 30, showing operative segment O (e.g. flexiblesegment 42) and tool 18. FIG. 12 shows two coaxial catheters includingan outer shaft O1 (such as outer shaft 32) and inner shaft O2 (such asinner shaft 34). Also disclosed are two stainless steel cables,including outer cable O3 and inner cable O4. Outer shaft O1 providestranslational and rotary motion. Outer cable O3, which is disposedbetween outer and inner shafts O1 and O2, provides the lateral rotation(or yaw motion) of tool 18. Inner shaft O2 rotates tool 18 and innercable O4 actuates the jaws of tool 18. The tool of FIG. 12 provides asingle degree-of-freedom in order to actuate a gripper, scissors orgeneric mechanism (such as a stapler or clip applier). An example may bea bi-directional gripper 5 mm in length and 2.67 in diameter.

[0184] In one embodiment, the system comprising the flexible instrumentcomprises tool or mini-tool (18), the operative segment (42), thecatheter stem (32, 34), the coupler (24, 26) comprising the mechanicallydrivable mechanism 26 and the receiver 24, the drive unit (13), thecontroller (12) and the surgeon's interface (11). The coupler provides atranslational degree-of-freedom achieved by using a sliding mechanism,i.e. rails 25, onto which the coupler is mounted, as illustrated in FIG.6. The operative or controlled flexible segment provides a number ofarticulations in order to position and orient tool 18. The catheter (30)has four (4) degrees-of-freedom, i.e. one translation and threerotations, as shown in FIG. 7. A fifth degree-of-freedom may be providedby the actuation of the mini-tool, as tool 18 can provide at least asingle axis of motion for a grasper, scissors or general mechanism (suchas a stapler or clip applier). The combination of one translation andtwo rotations allows the operative segment to arbitrarily position themini-tool in three dimensional space. A final degree-of-freedom rotatesthe mini-tool axially.

[0185] The following describes the mathematical mapping of thephysician's command input to the motion of the catheter system. FIG. 13schematically illustrates the various degrees of freedom by which thecatheter can be manipulated, particularly the axial and lateralrotations, or the translation motion allowing independent control of thetool position within the surgical space, as well as axial rotation ofthe tool. For example, the system of FIG. 6 provides a physician withseven independent command inputs, including position (χ_(i), γ_(i),z_(i)), orientation (θ_(i), ω_(i), ψ_(i)) and tool grip angle α_(i). Thecontroller calculates the position of the five (5) independentdegrees-of-freedom of the catheter system, given by (χ_(c), θ_(c),ω_(c), ψ_(c), α_(c)), by determining the position (x, y, z) of the tool,given by χ=χ_(c)+r cos ω_(c), γ=-r sin ω_(c) sin θ_(c), z=r sin ω_(c)cos θ_(c)ψ=ψ_(c)α=α_(c), where χ_(c), θ_(c), ω_(c), ψ^(c), α_(c) are theindependent inputs to the catheter system, and r is the distance fromthe lateral joint to tip of the mini-tool. The resulting position isχ_(c)=χ−r cos ψ_(c), θ_(c), =tan⁻¹ (−y/z), ω_(c), =sin⁻¹ (z/r cosθ_(c)), ψ_(c)=ψ, α_(c)=α If λ is chosen as a scaling value, thefollowing mapping between command input and independent catheter inputis x_(c)=λx_(i)−r cos ω_(c)θ_(c)=tan⁻¹ (−y_(i)/z_(i)), ω_(c)=sin⁻¹(λz_(i)/r cos θ_(c)), ψ_(c)=ψ, α_(c)=α It is noted that the axialrotation and grip position are not scaled.

[0186]FIG. 42 is a perspective view of another embodiment of the slavestation for a remote controlled flexible instrument. FIG. 42 depictsflexible instrument system 500 supported from support bracket 502, whichextend to the operating table (see FIG. 6). Usually the support bracketis supported from the side of the operating table and may be adjustablein position relative to the operating table, to dispose system 500 in aconvenient position over the patient. In one embodiment, bracket 502 issecured to the operating table at one end. The other end of bracket 502supports the entire flexible instrument by means of a two-piecestructure similar to that described in copending U.S. ProvisionalApplications Serial No. 60/279,087 filed Mar. 27, 2001. A knob may beprovided on support base 504, not shown in FIG. 42. Once the supportbase 504 is fixed to the support bracket 502, then the flexibleinstrument system is maintained in a fixed position at base 504,providing a stable and steady structure during the medical procedure.Like FIG. 6, system 500 can be positioned at an acute angle with respectto the operating table.

[0187] Flexible instrument system 500 comprises flexible instrument 510having a shaft 528 extending to mechanically drivable mechanism 526,which interlocks with base (or receiver) 506. Base 506 is supported oncarriage 508. Carriage 508 in turn is adapted for linear translation andsupported by elongated rails 512 and 514. Rails 512 and 514 terminate atone end via end piece 516, which provides further support. Support base504 terminates rails 512 and 514 at their other end. Carriage 508includes bearings or bushings 509 that support the carriage from rails512 and 514.

[0188] Flexible instrument system 500 employs two separate cable bundlesfor mechanically driving the flexible instrument along rails 512 and514. Pulley 521 (dotted outline), residing within carriage controlmodule 520, receives a first pair of cables 518. Pulley 521 alsoreceives a second set of cable (see cabling sections 513 and 515 ofcorresponding FIG. 43), which runs through carriage 508 to a furtherpulley 522 supported by end piece 516. The second set of cables controlsthe translational motion of carriage 508 and terminates at point 519(see FIG. 45).

[0189]FIG. 42 also shows a set of cables 524 for driving controlelements, e.g. pulleys within receiver 506. These control elements movethe shaft and the tool in several degrees-of-freedom. Arrow J1 indicatesthe linear translation via module 520. Rotational arrow J2 indicatesrotation of flexible shaft 528 of flexible instrument 510 about theinner axis parallel with the shaft length. Arrow J3 represents theflexing or bending of flexible shaft 528 at controlled flexible segment530. In this embodiment, flexible segment 530 is positioned directlyadjacent tool 534 at the distal end of shaft 528. Arrow J4 representsthe pivot action of a wrist joint, which links tool 534 to shaft 528,about axis 532. In this embodiment, tool 534 is exemplified as agrasper, and arrows J5 and J6 represent the opening and closing actionsof the tool jaws. Motions indicated by arrows J2-J6 are controlled fromcabling 524 originating at receiver 506.

[0190]FIG. 42A provides an enlarged perspective view of the distal endof shaft 528 including flexible segment 530 and tool 534. Tool 534comprises upper grip or jaw 602 and lower grip or jaw 603, bothsupported from link 601. Base 600 is affixed to or integral withflexible shaft 528. Link 601 is rotatably connected to base 600 aboutaxis 532. A pivot pin may be provided for this connection. Upper andlower jaws 602 and 603 are rotatably connected to link 601 about axis536 and again, a pivot pin can provide this connection.

[0191]FIG. 42A shows eight cables at 538 extending through the hollowinside of shaft 528 for control of tool 534 and flexible segment 530.Two of these cables operate the bend of flexible segment 530, two cablesoperate one of the jaws 602, two cables operate the other of the jaws603 and the last two cables operate the wrist action about the axis 532.All of these cables travel through the hollow shaft 528 and throughappropriate holes in flexible segment 530, e.g. wire 525, as well asholes in base 600. Each of these pairs of cables operates in concert toopen and close jaws, pivot about the wrist, and bend flexible segment530.

[0192] One pair of cables travels through shaft 528 and throughappropriate holes in the base 600, wrapping around a curved surface ofthe link 601 and then attaching to the link. Tension on this pair ofcables rotates the link 601 along with the upper and lower grips or jaws602 and 603 about axis 532.

[0193] Two other pairs of cables also extend through the shaft 528 andthrough holes in the base and then pass between fixed posts 612. Theseposts constrain the cables to pass substantially through axis 532, whichdefines rotation of link 601. This construction essentially allows freerotation of link 601 with minimal length changes in the cables passingto jaws 602 and 603. Thus, the cables actuating jaws 602 and 603 areessentially decoupled from the motion of link 601 and are not effectedby any rotation of link 601. Cables controlling jaw movement terminateon jaws 602 and 603. These cables permit independent operation of thejaws 602 and 603 in respective clockwise and counter clockwisedirections with respect to axis 536. A similar set of cables is presenton the under-side of the link 601 (not shown). Each of the jaws 602 and603, as well as the link 601, may be constructed of metal.Alternatively, link 601 may be constructed of a hard plastic material.Base 600 may also be constructed of a plastic material and may beintegral with shaft 528.

[0194] Bending of flexible segment 530 is provided via diametricallydisposed slots 662, which define spaced ribs 664. Flexible segment 530also has a longitudinally extending wall 665 through which cabling mayextend, particularly for the operation of the tool. One of the pairs ofcables of bundle 538 controlling flexible segment 530 terminates wherebase 600 intercouples with shaft 528. This pair of cables works inconcert to cause bending as indicated by arrow J3, i.e. in a directionorthogonal to the pivoting provided at wrist axis 532. In FIG. 42A onlyone cable 525 of two is illustrated.

[0195]FIG. 43 is an exploded prospective view showing carriage 508,receiver 506 and drivable mechanism 526. Carriage 508 is adapted formotion along rails 512 and 514. Pulleys 521 and 522 receive cabling,i.e. cable sections 513 and 515, which terminate at the carriage base atpoint 519. Other sections of this cable extend through an elongated holeor passage within carriage 508.

[0196] Receiver 506 and drivable mechanism 526 each comprise enclosedhousings supporting a plurality of control elements, such asintercouplable drivewheels and associated pulleys or cams.Inter-engaging gears 540 and 542 are supported respectively in themodules 506 and 526. A pair of cables from bundle 524 engages pulley 544(see FIG. 45) which, in turn, drives gear 540, and which further, inturn, drives gear 542 for providing rotation of shaft 528. Collar 546 isprovided at the terminus of the proximal end of shaft 528 for supportingshaft 528, which is driven by gear 542. Cabling extending through collar546 and shaft 528 couple mechanical actions from drivable mechanism 526through the flexible instrument shaft 528 to the distal end thereof.

[0197] Drivable mechanism 526 interlocks with receiver 506, providingthe mechanical connection that allows the drive unit to run cabling inflexible instrument 510. Blades 606, jutting out from the housing ofreceiver 506, engage with corresponding slots 608 associated withdrivable mechanism 526. Projecting from the proximal end of receiver 506is ridge 610, which is substantially U-shaped and provides anotherinterlocking feature for mating with a similarly shaped slot 614 at thesame end of drivable mechanism 526. Posts 616 protruding from thehousing of receiver 506 are adapted to releasably mate with holes 618 indrivable mechanism 526. Posts 616 and holes 618 to interlock with eachother, but may be released from each other via side-disposed buttons620, as illustrated in FIG. 46. FIG. 43 also shows the cam lockingscrews 615.

[0198]FIG. 44 is a partial broken away rear elevational view ofinterlocking interfaces as seen along line 44-44 of FIG. 42. FIG. 44shows alignment posts 616 each having a groove 617, which is engaged bythe corresponding button 620. Button 620 is in the form of a platemember biased to a locked position by means of spring 621. A plate forbutton 620 has a keyhole slot for receiving and holding post 616therein. Button 620, however, may be manually depressed to release posts616 and enable ready detachment of drivable mechanism 526 from receiver506. A retaining pin 625 may also be used to limit the travel of thebutton between in and out positions.

[0199]FIG. 45 is cross-sectional side view through the interconnectingmodules taken along line 45-45 of FIG. 42. FIG. 45 shows details ofdrive wheels (or pulleys) in the modules 506 and 526. Four drive wheels622 are supported within the housing of receiver 506. Drive wheels 622receive cabling for controlling the motions of the shaft and the tool,where the cable protrudes from cable bundle 524 in FIG. 43. Each ofthese pairs of cables is controlled from a corresponding motor, which ispart of the drive unit (see discussion of FIG. 49, below).

[0200]FIG. 45 also shows output blades 606, previously shown in FIG. 43,which extend into corresponding slots 608. These slots are disposed inrespective intergaging drive wheels 624 of the drivable mechanism 526.Blades 606 have a rectangular end construction for engaging with similarrectangular slots 608 associated with the module 526. FIG. 45 also showsthe gears 540 and 542 in engagement to allow drive to occur from bundle524.

[0201]FIGS. 45 and 46 show a series of idler cams 626, one associatedwith each of drive wheels 624. FIG. 46 is a plan cross-sectional planview through receiver 506 as taken along line 46-46 of FIG. 45. FIG. 46shows the placement of cams 626. A cable wraps around each of drivewheels 624 and is held in position by its associated cam 626. FIG. 46also shows all of the cables running parallel to each other at region627, where the cables run from respective drive wheels 624, throughcollar 546 and extending down inside shaft 528 to the distal end. Withthe use of the placement and adjustment of cam 626, the cables are alldirected in a manner to easily couple into shaft 528.

[0202] Each of cams 626 has an off-center axis 631. As viewed in FIG.46, cam 626 may be rotated clockwise to tighten its associated cable.Rotation counterclockwise loosens the tension. Cam locking screws 615secure cam 626 in an adjusted-to position (see FIG. 48, across-sectional view taken along line 48-48 of FIG. 47). FIG. 48A is across-sectional view taken along line 48A-48A of FIG. 48. As depicted inFIGS. 46 and 48A, the cable associated with each wheel 624 may besecured in a cable clamping hole 633 via a cable clamping screw 635. Asimilar clamping arrangement is associated with wheels 622. A roll pinfixes each wheel 622 to each spindle 607.

[0203]FIG. 47 is a cross sectional plan view taken through receiver 506,as taken along line 47-47 of FIG. 45. The cross-sectional view of FIG.47 illustrates drive wheels 622 associated with receiver 506. Drivewheels 622 receive cabling from cable bundle 524. Each of a pair ofidler pulleys 630 are associated with drive wheels 622. At the veryinput to receiver 506, idler pulleys 632 are used for directing thecable to idler pulleys 630 and from there to drive wheels 622.

[0204]FIG. 48B is a fragmentary plan view of a drive wheel engagementslot by itself as seen along line 48B-48B of FIG. 48A. Thecross-sectional views of FIGS. 48A and 48B illustrate drive wheels 622within receiver 506 having associated end blades 606. End blade 606 is ascrewdriver-type blade that engages a slot previously identified as slot608 in FIG. 43. This slot 608 is in drive wheel 624 of receiver 526. InFIG. 48B, slot 608 displays a tapered portion. The tapered portionallows easy registration of end blade 606 and slot 608, and thus easyregistration between drive wheel 622 and drive wheel 624.

[0205] As described to this point, the bending or deflection of theshaft can be actuated by mechanical means such as a wire extending alonga length of the shaft. Thus, actions at the distal end of shafts may becontrolled by mechanical elements, such as cables, wires or othertendons.

[0206] Alternatively, actuation of the controlled bending can occur byother means, such as by remote electromagnetic signal couplings. FIG.41A illustrates shaft 850 having a central lumen. Residing in thecentral lumen is an operative or controlled flexible segment O, in theform of a plurality of spaced electromagnetic rings 852, separatelylabeled as R1, R2, R3 and R4. Each of rings R1-R4 is associated withwires 854, similarly labeled as wires W1, W2, W3 and W4. Rings 852, onceenergized, provide bending of shaft 850 at flexible segment O. FIGS. 41Aand 41D are meant to be schematic, while FIGS. 41B and 41C are actualimplementations for actuation of the rings by means of coils or windings853. As illustrated in FIG. 41B, each ring may be electrically energizedvia a winding 853 associated therewith. FIG. 41B shows a fully woundwinding, while FIG. 41C shows a half wound winding. Ring 852 may alsohave two separate half wound coils on opposite sides thereof. Wires 854(in pairs) are selectively energized to energize windings 853 on therings, which in turn, provide either attraction or repulsion of therings. FIG. 41D illustrates the results of regions of rings 852 beingenergized to attract or repel adjacent rings. For example, a certaindirection of current flow through windings 853 can create an attractionof the coils at the bottom and a repulsion of coils at the top. Thiscooperative action causes a bending at the operative or controlledflexible segment O.

[0207] The flexible instrument depicted in FIGS. 6 and 7 provides onlythe distal end as being remotely controlled. It can readily beappreciated that a controlled flexible segment may be provided, notnecessarily for action at a target site, but to control certainmovements of the catheter to assist in reaching a target site.

[0208]FIGS. 4 and 5 illustrate the advantages of a flexible instrument,particularly a catheter having controlled flexibility via controlledflexible or operative segments, for use in performing a procedure or forguiding the instrument through a natural body lumen. FIG. 4 provides aschematic cross-sectional diagram, illustrating a catheter K for use inmitral valve repair, to be discussed in more detail below. FIG. 4 alsoshows catheter K supporting a tool 18 for carrying out certainprocedures at the mitral valve annulus, also described in further detailbelow. In FIG. 4, catheter K is shown entering the femoral vein V by apercutaneous access at S. From the femoral vein V, catheter K must bendprior to entering the right atrium R. Catheter K then passes through aseptal wall of the heart to the left atrium L, which is directly abovethe mitral valve M. In this particular embodiment, the operative segmentof the catheter K is illustrated at O and is positioned near the verydistal end of the catheter K. Thus, at the sharp, almost 90° bend priorto entering right atrium R, a user can controllably bend catheter K atthe operative segment, to perform a procedure with tool 18. Also, theability to controllably bend catheter K prevents tool 18 fromconceivably being trapped within femoral vein V, causing damage to thewalls of vein V. In this embodiment, it may be preferable to have atleast some length of catheter K constructed of a deformable or flexiblematerial, enabling the catheter to easily pass through the body lumen byessentially conforming to vein configurations, such as that of femoralvein V.

[0209]FIG. 5 provides a schematic cross-sectional diagram illustrating asurgical procedure where catheter K1 enters a natural body orifice, suchas the urethra for carrying out procedures in, for example, the bladder.In FIG. 5 catheter K1 is shown extending into bladder B1. In thisexample, the computer controlled segment, identified as operative orflexible segment O in FIG. 5, is positioned at a more proximal sectionof catheter K1. Bladder B1, being an open cavity, does not have lumensleading from the urethra that would naturally guide a catheter towardsany particular operative site. Upon entering bladder B1, catheter K1 canbend in any direction and not necessarily in the direction of theoperative site. In this embodiment, because of the more proximalpositioning of operative segment O, a surgeon can controllably bend thedistal end of catheter K towards the operative site. In the embodimentshown in FIG. 5, the distal end of the catheter, labeled P1, can berigid or be “passively” flexible, i.e. made of a flexible material andnot necessarily controlled for flexure under remote computer control.

[0210] In the illustration of FIG. 4, the catheter K may be fed throughthe femoral vein by direct surgeon manipulation, in which case only theoperative segment O is under computer control from a master station.Alternatively, the catheter may translate linearly through the veinunder remote master station control, where the catheter can have otheroperative segments disposed at different locations of catheter K. Eachof these operative segments can be controlled from a master station forassistance in the guiding of the catheter to a predetermined targetsite. Thus, the catheter may be inserted manually and also have remotecomputer control for at least limited linear translation.

[0211] FIGS. 3A-3C show different embodiments of flexible instrumentswith multiple operative or controllable flexible segments. Shafts havingmultiple operative segments can be very useful for procedures in a bodycavity, as discussed previously, but can also be useful in navigatingthe shaft through intricate or delicate body lumens. FIGS. 3A-3Cschematically illustrate controller CT and a slave portion of the systemcomprising actuators or drive units A1-A4 and shaft KA, KB or KC havingthree operative segments O1-O3. In accordance with each of theseembodiments, a surgeon inputs commands from a master station to causecertain corresponding movements of the shaft at the slave station. Asurgeon's manipulations at the master station are coupled to controllerCT where these manipulations are mapped to actions at operative segmentsO1-O3. Thus, a surgeon, at an appropriate input device, may carry out afirst manipulation to control a segment O1, a second differentmanipulation to control the segment O2 and still a third manipulation tocontrol the segment O3, either simultaneously or sequentially. A fourthmanipulation may control the tool G.

[0212]FIG. 3A shows shaft KA having three operative segments, O1, O2,and O3, and tool G at its distal end. Actuators A1, A2 and A3 areassociated respectively with operative segments O1, O2 and O3. ActuatorA4 controls tool G. Each of actuators O1-O3 is controlled fromcontroller CT. Operative segments O1, O2 and O3 are spaced a certaindistance apart from each other, allowing shaft KA to simultaneouslyexperience controlled bends. This arrangement may be necessary forlumens with multiple bends, or for hard to reach operative sites.

[0213]FIG. 3B, shows catheter KB having tool G1. In this embodiment,three operative segments O1, O2 and O3 are spaced from each other alongthe length of catheter KB. Segments O1-O3 can be controllably bent toform an arc having an imaginary radius point P. Thus, this arrangementof operative segments can actuate particularly acute bends. In anotherembodiment, catheter KC in FIG. 3C employs three operative segmentsO1-O3, which are contiguous. The radius of curvature can be increased.

[0214] It is understood that non-operative segments of the catheter inFIGS. 3A-3C can comprise either a flexible or a rigid material. It canbe appreciated that one or more controlled flexible segments can beincorporated in the shaft, depending on the particular application.

[0215] Another aspect of the present invention provides a remotecontrolled flexible instrument operable within the sterile field, anddisposable after use. The sterility of reusable medical instruments andimplements are maintained by well-known methods such as exposure tosterile solutions and/or autoclaving. For some medical implements, itcan be more cost effective to manufacture them from low cost materialsand dispose them after a single use, or use on a single patient. But forcertain other medical instruments, its manufacture from low costmaterials still results in a costly product due to the intricate natureof the individual parts and the labor required to manufacture complexcomponents.

[0216] It is another feature of the present invention to provide adesign for a remote controlled flexible instrument having disposablecomponents, particularly those components that are exposed to thesterile field. The present design allows the use of injection-moldedplastic parts. The disposable component can be easily and quicklyengaged into and disengaged from a non-disposable, reusable base. Thecomponents can be locked onto the base by snapping or interlockingmatched parts, without having to thread cable wires or attach anyintricate components.

[0217] One aspect of the present invention provides a disposableimplement comprising a disposable mechanically drivable mechanism, adisposable shaft extending from the drivable mechanism, and optionally adisposable tool supported on a distal end of the shaft. Referring backto FIG. 7, mechanically drivable mechanism 26 comprising gears 60 and 68and pulleys 64 and 72, can be manufactured from injection moldedplastic, as well as shaft 30 extending from drivable mechanism 26. Thesides of pulleys 64 and 72 feature a first semicircular planar discstepped up from a second matching semicircular planar disc. The sides ofthe pulleys in receiver base 24 correspondingly match the stepped uppattern of pulleys 64 and 72. Engaging drivable mechanism 26 ontoreceiver 24 requires matching and interlocking the respective pulleydiscs. Thus, the interlocking feature in effect extends the cablingpathway from the first set of cables running from the drive unit toreceiver 24, to a second separate set of disposable cables containedwithin drivable mechanism 26 and shaft 30. No tying or threading ofcables is required to engage the disposable portion onto receiver 24.

[0218] Another design for a disposable implement is illustrated in FIG.42. In FIG. 42, the flexible instrument 510, comprising drive mechanism526 and shaft 528, can be a single piece disposable unit that is readilyengageable and disengageable relative to the base module 506.

[0219] Disposable implement 510 may be considered as comprising adisposable, mechanically drivable mechanism such as the coupler ormodule 526 interconnected to a tool 534 through an elongated disposableflexible shaft or stem 528. This disposable and flexible implement ismounted so that the mechanically drivable mechanism may be connectableto and drivable from a drive mechanism, such as illustrated in FIGS. 6and 7. In the illustrated embodiment the drive mechanism may beconsidered as including the coupler or module 506 and the associateddrive motors. The disposable elongated flexible instrument is generallyinserted into a body vessel or cavity of a subject along a selectedlength of the disposable elongated instrument with the elongatedflexible instrument being disposable together with the disposablemechanically drivable mechanism.

[0220] The disposable implement is purely mechanical and can beconstructed relatively inexpensively thus lending itself readily tobeing disposable. It may be difficult to make only the tool disposable,due to the intricate nature of the tool parts, which may require theuser to perform intricate maneuvers and cable threading into the base ofthe slave station. Here, the disposable implement, i.e. the tool, shaftand drivable mechanism are manufactured as a single piece disposableunit, thus eliminating the need for intricate instrument or toolexchange procedures.

[0221] Ideally, the base of the slave station, which contacts thedisposable implement, is easily cleanable. It is preferred that thedisposable implement, which operates within the sterile field,experiences minimal contamination by contacting the slave station. Inone embodiment of the present invention, as illustrated in FIG. 43, theinterlocking drivable mechanism 526 and receiver 506 featuressubstantially planar surface at the point of contact between the twomodules. Regarding receiver 506, the planar surface is easy to clean andthe inner intricate pulleys and cabling are protected from contaminationby the housing. Regarding mechanically drivable mechanism 526, thehousing can be made of injection-molded plastic that is simple tomanufacture and is easily disposable.

[0222] One advantage of the present invention is the ease of engagingand disengaging the disposable implement. In a particular medicalprocedure, a multitude of instrument exchanges may be required, and thesystem of the present invention is readily adapted for quick and easyinstrument exchange. Because the receiver is maintained in a fixedposition, the surgeon can easily exchange instruments by readilydecoupling at the modules 506 and 526. The ease of exchanginginstruments lends to the portability of the slave station. This portablenature of the slave unit comes about by virtue of providing a relativelysimple flexible instrument in combination with an adaptor (module 506,module 520, carriage 508 and associated components) for supporting theflexible instrument. Overall, the slave station is of a relatively smallconfiguration. Because the slave unit is purely mechanical, and isdecouplable from the drive unit, the operator can readily position theslave unit. Once in position, the slave unit is then secured to thesupport, and the mechanical cabling of the slave unit is then attachableto the drive unit. This makes the slave unit both portable and easy toposition in place for use.

[0223]FIG. 49 shows an embodiment where pulley 677 is readily manuallydecouplable from motor 675. For this purpose pulley 677 may be atwo-piece pulley arrangement comprising a coupler spindle and a couplerdisk with the coupler disk secured to the output shaft of the motor.This enables the entire assembly to be disconnected at the motor so thatthe flexible instrument system 500 with its flexible instrument 510 maybe positioned relative to the patient, independent of any coupling withthe drive motors. Once the system illustrated in FIG. 42 is in place,then the coupling of the cables can be made at pulley 677 to providedrive to the flexible instrument system.

[0224] Another aspect of the present invention provides a system forrepairing a cardiac valve, such as a mitral valve. Current mitral valverepair techniques, either open or minimal access, require the surgeon toplace the patient on cardiopulmonary bypass and stop the heart. The leftatrium is then opened and exsanguinated to allow the surgeon to performthe repair. This aspect of the present invention provides a minimallyinvasive mitral valve annuloplasty technique featuring the followingadvantages: (1) peripheral venous access; (2) the heart can continue tobeat during the repair; and (3) assessment of the correction of valveincompetence in real-time using, for example, Doppler ultrasoundguidance.

[0225] In one embodiment, the present cardiac valve repair systememploys a guide shaft extending from a site outside a patient to an areaabout the cardiac valve. The guide shaft receives a flexible inner shaftfor disposing a tool at the area about the cardiac valve, where the toolis supported at the distal end of the guide shaft. Preferably, the innershaft has a relatively small diameter enabling percutaneousintravascular and endoscopic surgery. Even more preferably, the innershaft, and optionally the guide shaft, is capable of accessing themitral valve from the peripheral circulation, eliminating the need forincisions through the chest wall. In one embodiment, the inner shaft canhave a diameter ranging from 8 to 15 French (2.5-5.0 mm). The outercatheter may be constructed from a standard 9 French coronary guidecatheter, having a diameter of 2.67 mm and a wall thickness of 0.1 mm.In other embodiments, the inner catheter can have an outer diameter of1.1 mm and an inner diameter of 0.09 mm. In yet another embodiment, thebraided stainless steel cables are 0.63 mm in diameter and are capableof transmitting 178 Newtons (40 lbs. approx.).

[0226] A feature of this aspect of the present invention is that thepercutaneous access to the mitral valve can be accomplished on a beatingheart, eliminating the risks associated with cardiopulmonary bypass(CPB). To enable a procedure on the beating heart, preferably theprocedure can be performed under physiologic conditions. The physicianmay monitor the procedure by, for example, transesophagealechocardiography, instead of a video image. This technique enablesreal-time assessment of the correction of the mitral valve regurgitation(MR) during the procedure, further enabling intra-operative provocativecardiac testing, with preload and afterload challenges and cardiacpacing all under trans-esophageal echo and trans-thoracic ultrasoundguidance to optimize repair.

[0227] The tool can be remote controlled, as described herein, and canbe designed for use in any procedure of the cardiac valve repairprocess. For example, a first set of tools is capable of percutaneousmitral valve annuloplasty. This represents a paradigm shift inmanagement of disease from MIS and open surgical to intraluminalinterventions. While this catheter-based intervention is described inconnection with mitral annuloplasty, the technique can also be appliedto other structures such as, by way of example and not limiting, thebilliary tree, the genitourinary tract and intraventricularneurosurgery.

[0228] The system further includes a retainer at the area of the cardiacvalve, where the retainer is attached to an annulus of the cardiacvalve. As will be described in greater detail below, the retainer iscloseable via the tool to draw the annulus into a smaller diameter.

[0229] In one embodiment, a trans-septal guide catheter is used to guideand support an inner catheter. The guide catheter is introduced bypercutaneous access, and allows the clinician to access the left atriumvia the venous circulation, i.e. through the heart wall (see FIG. 4).The guide catheter may be non-robotic, i.e. simply manipulated manuallyby the surgeon. Alternatively, the guide catheter may be roboticallycontrolled from surgeon manipulations at an input device of the masterstation.

[0230] Once access to the left atrium is established, the inner catheteris threaded into the left atrium through the guide catheter. The innercatheter contains attachment anchors for deployment at desired pointsaround the mitral valve annulus. A remote controlled 5-degree-of-freedomtool and wrist can be utilized to precisely reach the annulus.Ultrasound may be used to visualize the system and guide the anchorpositioning and placement. This ultrasound may be trans-esophagealultrasound or trans-thoracic ultrasound, for example. Furthermore,electrophysiologic signals of the heart may be used to aid in preciselylocating the position of the tool at the fibrous mitral valve annulus.

[0231] There is now described a number of techniques employing thecatheter apparatus of the present invention. These techniques aredescribed herein primarily in connection with mitral valve repair.

[0232]FIG. 19 is a schematic representation of the heart muscle showingthe left ventricle 218, the right ventricle 219, the left atrium 220,the right atrium 221 and the aorta 222. Between the left atrium and theleft ventricle, blood flow is from the left atrium through the mitralvalve 210 to the left ventricle 218. FIG. 26 illustrates an expandedview of a mitral valve at 210 including annulus 211 and leaflets 213.FIG. 27 illustrates schematically the leaflets 213 of the mitral valve210 with the mitral valve annulus 211. As a heart muscle ages, it istypical for the annulus of the mitral valve 210, illustrated in FIG. 19at 211, to expand in diameter causing problems with the leaflets 213. Ifthe leaflets fail to close properly, regurgitation may result, causingleakage by the mitral valve in the reverse direction and resulting inimproper blood flow through the heart. Thus, mitral valve repairinvolves, at least in part, shrinking the diameter of the annulus toallow the leaflets to operate properly.

[0233] In one embodiment, threading or sewing a ring about the annulusreduces the annulus diameter, where the ring is closeable. The annuluscomprises relatively tough tissue just above the top of leaflets. Asviewed in FIG. 19, the opposite end of the annulus at 217 tends toexpand outwardly. FIG. 19 illustrates an area at the annulus of themitral valve (that annulus being at the top in FIG. 19) identified astrigone area 215, where the valve ring is more rigid and remainsstationary. Because this area is relatively stable and rigid, it is thusdifficult to contract, and most of the expansion of diameter of the ringoccurs away from the trigone area. This, again, is illustrated in FIG.20 by the positions shown in solid and in dotted outline.

[0234]FIG. 20 shows schematically parts of the heart such as the leftatrium 220 and the left ventricle 218, with the mitral valve 210disposed therebetween. FIG. 20 illustrates the annulus of the mitralvalve in solid position, at a smaller diameter where the leafletsoperate properly. The dotted outline 217 represents the expandeddiameter of the base of the mitral valve, the state at which mitralvalve leakage can occur.

[0235] To carry out the technique of the present invention, a guidecatheter 230 is employed, such as a transseptal atrial guide catheter.The access for catheter 230 is via the vena cava to the right atrium221. This access may be from above via the jugular vein or below by wayof the femoral vein. A puncture is made in the wall 238 of the rightatrium into the left atrium 220, allowing distal end 232 of catheter 230to pass into the left atrium 220.

[0236]FIG. 17 illustrates one method of shrinking the diameter of theannulus. FIG. 17 shows a metal wire ring 100 in place about the mitralvalve annulus. The ring 100 may be initially secured at the trigone area103 of the mitral valve annulus. The technique illustrated in FIG. 17may rely upon a catheter apparatus, such as depicted in FIGS. 6 and 7herein with an operative segment. At least limited linear translation ofthe catheter may be accomplished with an apparatus similar to thatdescribed in FIG. 6, although a guide catheter may also be manuallyinserted at least partially by the surgeon through percutaneous accessvia the femoral vein. The ring 100, although depicted in a ringconfiguration in FIG. 17, can be first inserted through the catheter ina straightened configuration. The metal wire or ring 100 is preferablyconstructed of a material such as Nitinol. The characteristics of thismaterial include the ability to retain its form or to be stretched to astraight position. Once the material is passed through the catheter, itcan spring back to its ring configuration. The surgeon preferablymatches the configuration of the ring, particularly as to its size, toprovide a proper fit for the particular mitral valve that is beingrepaired.

[0237] Once the straightened wire 100 has passed through the catheter,it assumes the position shown in FIG. 17. The ring, once in place, issecured to the annulus via wire clips 106 and/or sutures 102. By drawingon these sutures with the tool, the diameter of the mitral valve annulusis reduced so that it conforms to the size of the wire loop 100. As withother techniques described herein, the control is supplemented by visualconsiderations such as with the use of ultrasound orelectrophysiological feedback.

[0238]FIG. 18 provides another embodiment of the present inventionemploying a catheter system for mitral valve repair. FIG. 18 provides aschematic representation of a ring 210 of a cardiac valve, such as amitral valve. Fiber 212 is looped about or sewn around the annulus(base) of the valve. A number of different types of stitches may beused. The fiber may be a thread or a wire. In the embodiment of FIG. 18,the fiber is actually sewn through the annulus of the valve. After thefiber is sewn in this manner, tension is applied to ends 214 of thefiber. The tightening reduces the diameter of the ring, brings the valveleaflets into their proper position so as to avoid valve regurgitation.

[0239]FIG. 20 also illustrates a balloon 234 that may be supported atthe distal end 232 of the catheter 230. Once the catheter 230 is inplace, balloon 234 is inflated to further support the guide catheter inplace with the end 232 extending slightly into left atrium 220. Onceballoon 234 is inflated or opened, it can be snugged back against theseptal wall 238 between left atrium 220 and right atrium 221. The innerdiameter of the catheter 230 may be on the order of approximately 5 mmin diameter. FIG. 24 shows an enlarged view of catheter 230, with itsend 232 and the associated balloon 234 holding catheter 230 in place.

[0240] As an alternate to the use of a balloon 234, a malecot 236 may beused. This is a mechanical device with expandable wings, as illustratedin FIG. 25 and associated with catheter 230 so as to hold the end 232 ofthe catheter in place relative to the septal wall 238.

[0241]FIG. 20 also illustrates a flexible catheter 240 with itsassociated tool 242 extending from the guide catheter 230. Tool 242 maybe a pair of jaws operable for threading or sewing fiber. These jaws canbe controlled externally at a user interface by a surgeon. With regardto flexible catheter 240, reference is made to co-pending provisionalapplication, U.S. Ser. No. 60/269,200, as well as pending applicationPCT serial number PCT/US00/12553, filed Nov. 16, 2000, both documents ofwhich are hereby incorporated by reference herein.

[0242] In FIG. 23 reference is also made to the fiber 212 and an endpiece 245 that is secured to one end of the fiber 212. Fiber 212 isshown sewn through wall 247. FIG. 23 also schematically illustrates thetool 242 engaging the fiber 212.

[0243] After guide catheter 230 is in place with the balloon 234inflated to secure it in position, flexible catheter 240 is threadedthrough guide catheter 230 to a position just about the mitral valve, asillustrated in FIG. 20. Fiber 212 may also, at the same time, bethreaded through the catheter member 230 with end piece 245 beingaccessible for being secured to the valve ring. As illustrated in FIG.20, the beginning position of the threading or sewing of the fiber 212is at a position close to or at the trigone area 215 of mitral valve210.

[0244] After a single threading or sewing has occurred, such as in FIG.23, then the jaws of tool 242 loop stitch the fiber 212, which may be asmall but rigid wire, about the mitral valve in the manner illustratedin FIG. 18. Staples 249 may also be employed for holding the wire inplace.

[0245]FIGS. 21 and 22 illustrate another embodiment to secure an end offiber 212. In this embodiment, the end of fiber 212 is pulled so as toclose the diameter of the base ring of the mitral valve. FIG. 21illustrates guide catheter member 230 at its end 232, being held inplace against the septal wall 238 by balloon 234. Flexible catheter 240with its tool 242 has been withdrawn from catheter member 230.Double-walled structure 250 comprises coaxially arranged inner and outertubes 252 and 254. Fiber 212 extends through these tubes and carriestherealong a securing piece 256 and a retaining button 258. The innertube 252 is adapted to engage the retaining button 258 and the outertube 254 is adapted to engage the securing piece 256. FIG. 22 showssecuring piece 256 and retaining button 258, along with the fiber 212.

[0246] Initially, once the threading through the base of the valve ringis completed, the outer tube 254 engages securing piece 256 moving itdownwardly in the view of FIG. 21 while the fiber 212 is held inposition. This tightens the securing piece 256 against the other side ofthe trigone area 215, of FIG. 20. Once the diameter of the ring has beentightened, inner tube 252 is moved downwardly to engage retaining button258. Button 258 grabs fiber or wire 212 and at the same time retainingbutton 258 engages and interlocks with the securing piece 256. In thisway, both ends of the threaded fiber or wire 212 are secured roughly atthe positions illustrated in FIG. 20. The pulled fiber 212 causes themitral valve ring to draw into a smaller diameter such as the positionshown in solid, rather than the in-dotted position of FIG. 20.

[0247] Once the securing piece and the retaining button are firmly heldto the wire 212, then the member 250 may be withdrawn through the guidecatheter 230. The flexible catheter member 240 may then be reinsertedwith a different tool such as a pair of scissors for cutting the exposedend of the fiber 212.

[0248] Another possible technique for reducing the annular diameterinvolves a loop of cable that extends through hooks or anchors placed inthe annulus, as illustrated in FIG. 29. FIG. 29 shows the cable or wire120 and schematically illustrates the anchors at 125. In this techniquethe valve is reduced through a “lasso” technique, in which the cableexerts an equal force on all of the anchors. This technique uses anarticulate catheter preferably inserted through a guide catheter, suchas illustrated hereinbefore, to place the anchors one at a time into themitral valve annulus. The cable onto which the anchors are suspendedprovides the closing force when tensioned by the operator.

[0249] In one embodiment, the flexible instrument comprises a guidecatheter 150, as illustrated in the diagram of FIG. 30. Inner catheter155 houses an anchor and cable system depicted generally at 160,including tensioning cable 162 and anchors 164. Five degrees-of-freedomare provided: (1) rotary, (2) linear, (3) flexure motion with regard tothe guide catheter 150 as well as (4) linear and (5) rotary motion withregard to the inner catheter 155.

[0250] Guide catheter 150 may be approximately 8 French in diameter witha computer controlled flexible end portion, illustrated in FIG. 30 asoperative segment O. A computer controls three degrees-of-freedom withregard to the guide catheter 150, along with two degrees-of-freedom ofinner catheter 155. Refer to FIG. 30 and the corresponding motionsF1-F5.

[0251]FIG. 30 depicts anchors 164 as having a loop and two legs,although other anchor designs can be readily contemplated. The legs ofeach anchor 164 may curl outwards. Once anchors 164 are deployed fromthe constraint of the inner catheter, they curl outwardly. The curlingmotion of the anchor legs secures them to the fibrous tissue of themitral valve annulus. Preferably the anchors are fabricated from asuper-elastic material such as Nitinol.

[0252] A tensioning cable, such as the cable or wire 162 illustrated inFIG. 30 may pass through each of the loops of the anchor. This allows anequal force to be placed on each anchor and prevents the anchors frombecoming loose in the bloodstream. The tensioning cable passes backthrough the robot inner catheter and out of the patient. The finaltension is adjusted manually by the surgeon (or by computer) to optimizethe annular size under direct visualization. Also, within the innercatheter is preferably disposed a deployment wire used to advance andfire the anchors into the annulus wall.

[0253]FIGS. 30A and 30B depict a cable termination tool set. This setcomprises two catheters used to: (1) crimp the end of the tether cableonce the tension is placed on the annulus; and (2) cut off the remainingcable at the end of the procedure. Both of these catheters may use afour-bar linkage or other system.

[0254]FIG. 30A shows a crimp tool 172 having a pair of jaws 174 that canbe used to crimp member 176 about the tether cable 170. Thus, the firstcatheter 172, which may be referred to as a cable crimper, holds thecrimp element 176 in the jaws 174 with the tether cable 170 pre-threadedthrough the crimp element and catheter shaft. The tensioning of thecable may be performed under ultrasound guidance. Although one tethercable 170 is shown in FIG. 30A, opposite ends of the tether that comefrom the mitral valve site preferably extend through the crimp element176. Once the tether cable is tensioned, so as to bring the mitral valveinto its proper diameter, then the crimp element 176 is actuated by thecable crimper 172 illustrated in FIG. 30A. Once the proper tension isachieved, the crimper is actuated by applying tension on the push-pulldrive cable 175 and by closing the crimp element at the jaws 174 so thatthe crimp element crimps the tether cable 170 in the proper position andat the proper tension.

[0255] After the crimping or securing step, then the cable crimper isremoved and the cutting catheter 182 is introduced as also illustratedin FIG. 30B. This catheter is also introduced over the tether cable 170and through the guide catheter. It is advanced up to the crimp, andsevers the cable with its jaws 184 by tensioning the push-pull drivecable 185. The procedure is now completed and the system catheters arethen removed.

[0256] As indicated previously, the proximal end of the catheter iscomprised of a disposable coupling mechanism that engages a drivemechanism, such as is shown in FIGS. 6 and 7. For this purpose, thecoupler, identified in FIGS. 6 and 7 as couplers 24 and 26 are adaptedfor disengagement therebetween. One coupler section may be considered astransmitting motion to the guide catheter while the other couplersection may be considered as transmitting motion to the inner catheterand the drive cable. This involves the mechanical coupling of the guidecatheter with the coupler so that actions of the guide catheter arecontrollable from the mechanical control elements of the coupler.

[0257] In one embodiment, a drive unit is coupled with the inner shaftand the guide shaft independently, the drive unit capable ofindependently effecting movement of each shaft to at least one degree offreedom.

[0258] For each coupler element, rotary disks transmit motion from theremotely controlled drive system to the catheter articulations. By wayof example, in a first coupler element, a horizontal disk may drive thedistal flexure. Another element may include disks, which control theaxial and/or rotary positions of the inner catheter and, for example,the advance of the anchors. All of the coupling elements are mounted ona slider or sliders, which allows independent control of the linearadvance of the outer and inner catheters. Again, refer to FIGS. 6 and 7.The catheter system including the inner and outer portions, as well asthe proximal coupling element are disposable and mount removably to thedrive member.

[0259] In accordance with the technique, such as described in FIG. 29,when the last anchor is in place, the inner robot catheter anddeployment wire are removed. The physician can manually (or undercomputer control) adjust the tension in the cable and thus the diameterof the mitral valve after the first element of the cable terminationsystem is threaded over the cable and through the robot guide catheter.Since this procedure is performed on a beating heart, the annular sizecan be optimized under direct ultrasound guidance. Once the mitral valveannulus has been precisely adjusted, a cable termination system, such asthe one depicted in FIGS. 30A and 30B, clamps and cuts the cable. Thiscompletes the mitral valve repair procedure.

[0260] Another feature of the present invention provides a system forclosing the base of a cardiac valve, such as a mitral valve. The closingcan occur primarily by a stapling technique in which staples areattached to the valve ring or annulus to draw the annulus into a smallerdiameter. In this way the leaflets are then more appropriatelypositioned for opening and closing.

[0261]FIG. 31 illustrates a staple array comprising delivery system 342including storage housing 349 for a plurality of staples 350. Each ofstaples 350 is a surgical staple movably mounted within housing 349.Cable or wire 312 interconnects and loops through each of staples 350.Each staple 350 includes a pair of pointed ends 351 and center loop 353.The staple 350 at the most distal end of housing 351 (i.e. nearest theexit of housing 351) has cable 312 attached fixedly at loop 353, toprevent losing staples in the subject. For the remaining staples, cableor wire 312 freely loops through center loop 353. A release mechanism,not illustrated in FIG. 31, but which may be a standard design, can beused to move staples 350, one at a time, out of the housing 349. FIG. 31also schematically illustrates a clamping mechanism 352 at the distalend of housing 349, for closing each of staples 350 as they exit housing349.

[0262]FIG. 32 illustrates another method for repairing a mitral valve,featuring the use of staples to secure a ring to the mitral valveannulus. As will be described in further detail, a tether cable orfilament is threaded through an array of staples or anchors via a firstinner catheter. Once the attachment anchors are placed around theannulus, the first inner catheter is removed and a second inner catheteris disposed in the guide catheter. This second inner catheter allows theclinician to apply tension to the cable to reduce the mitral valveannulus circumference, in effect, pulling on a lasso. The annuloplastyis monitored by real-time echocardiographic quantitation of regurgitantflow attenuation, with and without after-load reduction. The clinicianmonitors the cardiac physiology for resolution of regurgitation. Whenthe hemodynamics are optimized, still a further inner catheter devicemay be used so as to place a stop or crimp on the cable. Still anotherinner catheter device may be used to cut the cable. These latter twoinner catheter devices may be robotic or non-robotic catheters.

[0263]FIG. 32 features mitral valve 210 with trigone area 215. Guidecatheter 330 accesses the vena cava and passes to the right atrium 221.This access may be from above via the jugular vein or below by way ofthe femoral vein. A puncture is made in septal wall 238 separating rightatrium 221 from left atrium 220, allowing distal end 332 of guidecatheter 330 to access left atrium 220.

[0264] Balloon 334 may be supported at distal end 332 of guide catheter330. Once guide catheter 330 is positioned at a desired location,balloon 334 is inflated to secure guide catheter 330 to the wall withend 332 extending into the left atrium. Once balloon 334 is inflated, itcan be snugged back against the septal wall between left atrium 220 andright atrium 221. The inner diameter of the catheter 330 may be on theorder of approximately 5 mm in diameter. As an alternative to balloon334, a malecot may be used, i.e. a mechanical device having expandablewings capable of securing catheter 330 against septal wall 238.

[0265] Guide catheter 330 coaxially nests flexible catheter 340 and itsassociated staple delivery system 342. With regard to this catheterconstruction, reference is made to a co-pending provisional application,Serial Number 60/269,200 filed Feb. 15, 2001, as well as pendingapplication PCT serial number PCTIUS00/12553, filed Nov. 16, 2000, bothof which are incorporated by reference herein in their entirety.

[0266] After balloon 334 is inflated to secure guide catheter 330 inposition, flexible inner catheter 340 is threaded through guide catheter330 to a position just above mitral valve 210, as illustrated in FIG.32. Delivery system 342, associated with inner catheter 340, also passesthrough catheter 330, holding fiber 312 and staples 350 to an area aboutthe mitral valve.

[0267]FIG. 32 also illustrates fiber 312 tracing a circumference aboutannulus 211, terminating at two end locations 345 and 356. The areatraced by fiber 312 and where the stapling occurs is at a ring ofrelatively tough tissue just above the top of leaflet 213. The area nottraced by fiber 312 is valve trigone area 215, which is relatively fixedand not easily contracted. Thus, the repair of the mitral valve,involving decreasing diameter 217 from dotted line to solid line, occursaway from trigone area 215.

[0268] Flexible catheter 340 is manipulated to cause a stapling aboutannulus 211 of mitral valve 210. The releasing of each staple iscontrolled by a mechanism preferably within flexible catheter 340 andoperable from a user interface station remote from the subject. Once allof the stapling has occurred, wire 312 is pulled in the direction ofarrow 361 in FIG. 32. This pulling causes a closure of valve annulus211, as desired. Once the clinician is satisfied that the repair iscomplete, the cable 312 is then locked off with a crimp, such asillustrated at 365 in FIG. 33. This crimp may be facilitated by theinsertion of a different catheter member 340 within the catheter 330,all while the cable 312 is held in the proper cinched-down position.

[0269] A plurality of staples 350 having loops 353 encircling fiber 312,secures fiber 312 to the annulus of the mitral valve, terminating atpoints 345 and 356. The procedure of looping fiber 312 and stapling canbe performed via remote control from a master station under surgeoncontrol with multiple degrees-of-freedom of the tool so as to accuratelylocate the implant fiber 312 and staples 350.

[0270] Fiber 312 is fixedly secured to end staple 350 at point 345. Theremaining staples are free to glide along fiber 312. When all thestaples are secured about the annulus, fiber 312 may be cinched downunder ultrasonic guidance, watching for a reduction or elimination ofthe valve regurgitation. Once adequate tension has been placed on thecable 312, tension can be maintained without disengaging the closuresystem. This allows the clinician to monitor the patient for some periodof time to confirm that the repair has taken place. Once the clinicianis satisfied with the repair, the cable can be locked off with a crimpor by some other technique and the cable may then be cut.

[0271] Another feature of the present invention is that the techniquecan be performed under physiologic conditions. The physician can monitorthe procedure by, for example, transesophageal echocardiography, insteadof a video image. The aforementioned “lasso” technique enables real-timeassessment of the correction of the mitral valve regurgitation (MR) asthe “lasso” is tightened. This enables performance of intra-operativeprovocative cardiac testing, with preload and afterload challenges andcardiac pacing all under trans-esophageal echo and trans-thoracicultrasound guidance to optimize repair.

[0272]FIG. 33 illustrates an expanded view of the finished repairregion. A staple 350 is fixedly attached to fiber 312 at position 345.Pulling cable 312 through various loops 353 of staples 350 causespulling of the annulus into a smaller diameter, thus closing the valvefrom an initially larger diameter, dotted outline 217, to a smallerdiameter, solid outline in FIG. 32 at 217.

[0273] An alternate embodiment of a staple is illustrated in FIG. 34.Staple 362 may be an elastic-like staple, such as a nitinol staple.Staple 362 is normally biased to a closed position. A delivery systememploys rod 364, or the like, to hold staple 362 open. As the rod ismoved longitudinally to the array, each staple in sequence is sprungclosed. Such an arrangement would avoid the necessity of a clampingmechanism 352 as illustrated in FIG. 31.

[0274]FIGS. 35A and 35B illustrate other embodiments of an outercatheter 550 and an inner catheter 554 extending through septal wall560. These embodiments illustrate the outer (guide) catheter as arobotic catheter. It is understood that the instrument embodiments ofFIGS. 20 and 32 may also encompass systems where the guide shaft isrobotic. In FIG. 30, the guide catheter is also robotic. In FIGS. 35Aand 35B, arrow 557 indicates rotation of outer catheter 550, and arrow559 indicates flexing of outer catheter 550. In FIGS. 35A and 35B, innercatheter 554 can experience linear motion along the co-axis (arrow 562)and rotational motion (arrow 564). The outer catheter 550 may also becapable of independent linear translation. FIG. 35A illustrates innercatheter 554 as being capable of a controlled flex or bend, i.e. innercatheter 554 has a controlled flexible segment. Thus, the inner catheterof FIG. 35A is capable of deflecting in the direction of arrow 566.

[0275]FIG. 38 illustrates another embodiment of a catheter. Catheter 402supports dumbbell-shaped balloon 414. As illustrated in FIG. 39,catheter 402 can be introduced into the left ventricle 218 directedupwardly with balloon 414 disposed at mitral valve 210. The mitral valve210 separates the left ventricle 218 from the left atrium 220. As shownin FIG. 39, associated with the mitral valve is a ring of relativelytough tissue (the annulus) just above the top of valve leaflets 213.

[0276]FIG. 36 shows a cross-sectional view of the use of catheter 402and balloon 414 for mitral valve repair. FIG. 36 shows the plurality ofperipherally disposed anchor pins 405. FIG. 36A shows each anchor pincomprising a piercing end 426 and a loop end 428. A fiber or tether 408,as illustrated in FIGS. 36 and 37 extends through each of the loop ends428 and has its ends at 409 free to extend through the catheter 402 toan external site where the tether can be tightened, as will be describedin further detail hereinafter.

[0277]FIG. 37 also shows the position wherein pins 405 have beeninserted into wall 247, which is a section of the ring of the mitralvalve just above the leaflets. Pulling tether ends 409 together canclose the ring, thus pulling loop ends 428 into a smaller diameter. Thissmaller diameter reduces the diameter of the ring of the mitral valve soas to minimize or prevent valve regurgitation.

[0278] Initially, FIGS. 38 and 39 illustrates balloon 314 positioned ata desired location and in a deflated state. FIG. 38 illustrates pins 405disposed about a center section of balloon 414. In the rest or deflatedposition as illustrated in FIG. 38, the pins disposed at their mostinner diameter. This innermost diameter state is also represented in thecross-sectional view of FIG. 36. Tether 408 may extend by way ofcatheter 402 to an external site where it can be operated, e.g. outsidethe body.

[0279] Once the catheter and balloon are in place, such as illustratedin FIG. 39, the balloon is inflated by a balloon inflation lumen in thedirection of arrow 439 in FIG. 40. Arrangements for inflating balloonsare well known and are practiced, for example, in the angioplasty field.Inflation pressure may be coupled by way of the port 441 to the interiorof balloon 414 causing the balloon to expand. In FIG. 40 the balloon isshown only partially expanded. When fully expanded, the anchor pins 405extend to the ring just above the leaflets as indicted at 445 in FIG.40. The corresponding cross-sectional view is shown in FIG. 37,depicting the anchor pins 405 penetrating and anchoring the tissue. FIG.37 illustrates a placement of tether ends 409. As the trigone portion ofthe base ring of the mitral valve is the most stable portion of thering, it is preferred that tether ends 409 leave the loop atapproximately the trigone area. In this way the drawing in of thediameter of the ring is more effective.

[0280] After the anchors are seated, as illustrated in FIG. 37, tether408 can be tightened, thereby pulling the tissue together so as torepair the mitral valve and reduce or eliminate valve regurgitation.

[0281] Several different techniques may be used for guiding the catheter402. For example, transesophageal ultrasound or transthorasic ultrasoundmay be employed. Also, radiopaque dye fluoroscopy or electrophysiologictechniques may be employed for positioning of the catheter.

[0282] The tether can be placed about the mitral valve and tightened byusing coaxial inner and outer catheters. The concepts illustrated inFIGS. 39 and 40 may be practiced either with or without robotic control.

[0283] The aforementioned techniques for guiding the catheter may alsobe used for monitoring the effectiveness of the technique of the presentinvention. By monitoring the positioning of the balloon, one can assurethat the ends of the tether are preferably at the trigone area. Also, asthe tether is tightened, the surgeon may monitor the mitral valveactivity to determine whether the valve base ring has closed properly soas to reduce or eliminate valve regurgitation. Tether ends may besecured by knotting the ends thereof so as to hold the tether in aclosed position.

[0284] The techniques described herein may also be applied in othermedical procedures involving repair of other anatomic body members. Forexample, the techniques described in FIGS. 17-40 may be used in closing,tightening, or constricting other anatomic conduits including, but notlimited to, lumens, valves, or sphincters. One example is in connectionwith drawing the sphincter into a smaller diameter. This smallerdiameter is particularly useful in controlling “acid reflux” byconstricting an expanded sphincter that couples between the stomach andesophagus. By tightening the sphincter, stomach acids are restricted tothe stomach and don't pass back toward the esophagus. Access for such atechnique may be via the patient's mouth. Of course, the techniques ofthe invention may also be applied in virtually any other medicalprocedures performed internally on the patient.

[0285] The present invention provides a relatively simple system, bothin the construction and in its use. The capability to decouplecomponents at the drive unit and the receiver results in a readilyportable and readily manually insertable flexible instrument system thatcan be handled quite effectively by the surgeon or assistant when it isto be engaged with the patient. Only a minimal number of components arepositioned within the sterile field, enabling facile manipulation aboutthe surgical site. An advantage of the system of the present inventionis the decoupling nature of the system. In the system of the presentinvention, the instrument, drive unit and controller are inherentlydecoupled (attachable and detachable). The decouplable design enablesthe slave station to be readily portable. The instrument can bemaintained as sterile but the drive unit need not be sterilized.

[0286] The instrument of the present invention is relatively smallbecause the actuators are not housed in any articulating structure inthe system of this invention. Because the actuators are remote, they maybe placed under the operating table or in another convenient locationand out of the sterile field. Because the drive unit is fixed andstationary, the motors may be arbitrary in size and configuration.Finally, the design allows multiple, specialized instruments to becoupled to the drive unit, allowing a user to design the instrument forparticular surgical disciplines.

[0287] Having now described a limited number of embodiments of thepresent invention, it should now be apparent to those skilled in the artthat numerous other embodiments and modifications thereof arecontemplated as falling within the scope of the present invention.

1. A medical device comprising: a flexible guide shaft having a distalend disposed at a predetermined location in a subject; a flexible innershaft having a proximal end and a distal end supporting at its distalend a tool, the inner shaft being insertable into the guide shaft so asto dispose the tool at an operative site; and a drive unit coupled withthe inner shaft for providing controlled actuation of the tool, thedrive unit being remote controllably drivable by a user via a manuallycontrollable device.
 2. The device of claim 1, wherein the flexibleinner shaft includes at its proximal end a mechanically drivablemechanism drivably coupled to the tool.
 3. The device of claim 2,further comprising a mounting mechanism drivably intercoupled with thedrive unit, the mechanically drivable mechanism being readily mountableon the mounting mechanism for drivable intercoupling with the driveunit.
 4. The device of claim 3, wherein the drive unit is disposed at afirst location remote from a second location at which the mountingmechanism is disposed.
 5. The device of claim 3, wherein the drive unitcomprises a plurality of motors, each motor being readily drivablyinterconnectable to and disconnectable from the mechanically drivablemechanism.
 6. The device of claim 5, wherein the drive unit is readilymanually portable.
 7. The device of claim 3, wherein the mountingmechanism is readily engageable with and disengageable from themechanically drivable mechanism.
 8. The device of claim 7, wherein theflexible shafts extend to the mechanically drivable mechanism, theflexible shafts and mechanically drivable mechanism being readilymanually portable.
 9. The device of claim 1, wherein the guide shaftsupports an inflatable balloon, for holding the distal end of theflexible guide at the predetermined location.
 10. The device of claim 1,wherein the flexible inner shaft has a controlled flexible segmentcontrolled from the drive unit for controlling a bending action thereat.11. The device of claim 10, wherein the flexible guide shaft has acontrolled flexible segment controlled from the drive unit forcontrolling a bending action thereat.
 12. The device of claim 1, whereininner shaft and the tool is constructed and arranged as a single piecedisposable unit.
 13. The device of claim 12, wherein the flexible guideshaft is disposable.
 14. The device of claim 1, wherein the drive unitalso intercouples with the flexible guide shaft for controlled movementthereof.
 15. The device of claim 14, wherein the flexible guide shafthas controlled flexible segment and the drive unit controls bending atthe flexible segment of the flexible guide shaft.
 16. The device ofclaim 15, wherein the operative segments of both shafts are positionedabout their distal ends.
 17. The device of claim 1, further comprisingcabling extending along the inner shaft, controlled from the drive unit,and for actuation of the tool.
 18. The device of claim 1, furthercomprising an input device and a computation system coupled to the driveunit, the computation system capable of receiving commands from theinput device thereby operating the drive unit.
 19. A medical devicecomprising: a flexible inner shaft inserted within a flexible guideshaft, a tool being disposed at a distal end of the inner shaft forinsertion into a subject; a drive unit coupled with the inner shaft andthe guide shaft independently, the drive unit capable of independentlyeffecting movement of each shaft to at least one degree of freedom; anda user input interface remote from the drive unit, for remotecontrollably manipulating the inner and guide shafts.
 20. A medicaldevice comprising: a flexible guide shaft having a distal end disposedat a predetermined location in a subject; a flexible disposable innershaft having a proximal end and a distal end supporting at its distalend a tool, the inner shaft being insertable through the guide shaft soas to dispose the tool at an operative site; and a drive unit coupledwith the inner shaft for providing controlled actuation of the tool andcontrolled deformation of one or more flexible portions of the innershaft, the drive unit being remote controllably drivable by a user via amanually controllable device; wherein the proximal end of the innershaft includes a mechanically drivable mechanism drivably couplable tothe drive unit, the mechanically drivable mechanism being disposabletogether with the tool as a unit.